Watch Los Angeles get built, one building at a time (1880–2026)
lax-skyline.parcelscope.net205 points by rustywasm 6 hours ago
205 points by rustywasm 6 hours ago
As others have pointed out, this is more about the age of existing buildings than the construction of the city, but it's pretty neat.
About ten years ago when we were working on Mapbox GL, I did a mobile-native viz like this to show off the vector tile tech. The blog post is still up (thankfully) which has a good bit of info on the data processing pipeline as well, ranging from Shapefile to GeoJSON to vector tiles on the backend to Swift on the frontend:
https://medium.com/mapbox/visualizing-an-entire-citys-buildi...
I always loved mirroring a phone to a large TV and showing this off at 60FPS. It was such fun tech to work on.
It's amazing how little has changed in recent years in LA. The massive downzoning of the 1980s had its effect: prevent efficient land use, and channel money into the hands of landlords and homeowners from all newcomers.
LA is a ridiculously unaffordable place to live, not because it's nice, but because of an artificial shortage of built space, due to a monopoly on the permission to build.
>The massive downzoning of the 1980s...
To put numbers to this for those who aren't aware, LA was zoned for roughly 10 million people in the 1960s and by the 1980s it was zoned for roughly 4 million. It's part of the reason the city has had population growth slow to a crawl. It was decided some 40 plus years ago that LA should stay under 4 million people, so it has even til today. But the number of people who want to live in LA is constantly growing, so housing prices continue to rise and as a result lower income people are slowly but surely being pushed out of their homes and out of the city entirely.
Same story in San Francisco of course, and the rest of the US pretty much aside from a few cities in recent years.
And don’t forget prop 13, there’s negative incentive for property to change hands and develop.
Do people really think that if we revoked Prop 13 that other taxes would go down with the new money from property taxes?
Or do we think that property taxes would go up while other taxes stay put?
This feels like the argument at play when people criticize Prop 13. Not saying it’s good but California hasn’t ever cut taxes meaningfully and I’m not convinced raising property taxes would solve anything. California would still be expensive to live in.
Multiple good things would happen without prop 13:
People would move more instead of being locked in to a low effective property tax.
The tax burden would be much fairer: instead of the police and schools being funded by newcomers, everyone would be contributing their fair share to fund the city, instead of the longest tenure residents mooching off the rest of us.
Unproductive use of land would be discouraged. If a tract became highly desirable, it would be expensive to let it sit in an unproductive form
Cities could raise taxes as high as their residents wanted them to be, instead of being limited by the opinions of non-residents. Some people want to have better funded police and schools, and local government would actually be allowed to deliver that. Citizens who didnt want to live in expensive cities could vote with their feet to cheaper towns.
To keep tax revenue equal, property taxes for those who purchased recently would go down, and property taxes for those who’d purchased in the past would go up.
The housing market would become more liquid because people would move out of homes if their values rose too much and they could no longer afford the taxes. This would be a shock initially, but over time it would just be seen as part of life like it is in other areas: mostly, empty nesters would downsize to a cheaper, smaller house with lower taxes. Gentrification might be more problematic though.
In practice, probably some phased rebalancing would have to happen to avoid the sudden economic shock, but, politics notwithstanding, it’s not crazy to suggest it could be done and that the end state might be overall ‘better’ for most people. The end state would be how property taxes work almost everywhere else.
I've never heard anybody say anything like that when criticizing prop 13. It usually has more to do with housing prices and the fact that 2 people with the same home value should pay the same in property taxes. If you wanted to create a hereditary landed gentry, it would be hard to come up with a better policy to achieve that than prop 13.
Do you own your home? Here in Ca? You know that property tax is 1.4ish % and goes up by 2% a year, pretty much no matter what?
On a 1.5M house, that's starting at 17K a year and each year it goes up 2%, so it compounds.
That's 17k a year Just to stay in your own home.
People who don't pay property taxes here in ca, act like prop 13 means zero property taxes
Yes, your property tax is high ($17k) because of prop 13 - you are effectively subsidizing others who have sat on their residential and commercial property for 20-30+ years who are paying 25-50% of what you pay for any similar property in the same calendar year!
Your property tax goes up by 2% of your , guessing (relatively recent?) purchase price, and theirs goes up 2% of a much smaller base due to prop 13.
They have no incentive to move, downgrade. And they often use trusts to pass this tax base down to their kids. It’s feels like icky European feudalism.
Again i’m emphasizing that this goes for both residential and commercial buildings.
> It’s feels like icky European feudalism.
Pairs nicely with the permitting processes that basically boil down to "thou shalt pay the guild"
That is close to the average rate of inflation, though. Doesn't seem unreasonable to me.
They go up much more than 2% in literally every other state, California is the cheapest place to own property for >10 years.
You can argue against property taxes entirely, but Prop 13 definitely means that families, businesses, and all property owners work very hard to never sell, never reassess, and never change their tax rate.
While I think the goal of Prop 13 is laudable, a few reforms would cut some of the biggest downsides: it should be be for primary residences, where the named owner is the primary resident.
This would eliminate the tax break for commercial property, prevent it from being abused for second homes, and avoid the property trust shenanigans that have allowed some properties to change hands without a reset in the taxes paid.
I have a dumb question. What is the eventual of efficient land use? Say we bulldoze a bunch of single family homes and get 10x as dense. Now we have 10x as many people per square kilometer. Is that an efficient use of land? Will there be someone saying at 10x population density that it's an inefficient use of space? If yes, what would they propose instead?
Why are you acting like there isn't a definition of inefficient. I think "underutilized" is a pretty good definition.
The fact that every single person has a small private park in their front and backyards that's enjoyed maybe a couple hours per day at most is pretty wasteful - if it was shared the utilization would go way up and space used would be way down. Same goes for all the parking lots needed to facilitate car traffic - if we used more efficient/shared options like buses or trams then the parking lots that sit empty most of the day could be replaced with more businesses or houses that allow people to live closer to the services that they need every day.
Meanwhile, we have big bottlenecks in our city downtowns where all the density is packed. Spread that out and things get a lot more efficient - your commute probably goes down too because you can live closer to work. Suburbs don't work without a productive city near them - otherwise they're just rural areas.
this is the same fallacy of saying there's no point getting a 10x faster server because you'll just have 10x more load and your site will still be slow.
Yes, dense cities are more efficient in every way compared to sprawl. Can you articulate what is confusing about this?
To be fair NYC has taken the opposite approach and rents are extremely high there as well
NYC has had so much downzoning too. The icon of the city, the Empire State Building, now has a floor area ratio about double what’s permitted in that district. Many historical buildings, just like ESB, simply could not have been built today under current zoning regulation.
The city’s original 1916 zoning regulation permitted a hypothetical maximum population of 55 million; after WWII the new zoning regulations essentially limited hypothetical maximum population to a little more than 10 million if everything is fully developed. Recent initiatives like City of Yes did too little to reverse the trend.
Everything has a gigantic depends* on it when it comes to RE. People want to find one reason why things are bad, but it is always a big bag of mixed things.
When I was in Vancouver, people kept saying if we got rid of rent control, houses will be built, rent will come down. But houses are expensive to build, and they need to make money asap in the “exit economy”. They won’t come up easily, unless they make it cheap to build, which isn’t happening. Rents just started coming down, but so far insignificant amount (I just checked, a place I paid $2500 for in 2019, is going for $3300 after the decrease!), and demand curbing had more influence on it. Personally, I think we shouldn’t force people to move to a different area because rents skyrocketed. I’m all in support of getting paid out though.
People look at Tokyo, and talk about “less-zoned build whatever, and no rent control, thus more or less affordable”. Which also depends*. YoY rents are going up by 10-15% right now, even more in some areas. It’s unreasonable for a good chunk of residents. Speculation is big influx of money from China. But you can actually challenge the rent increase in a good chunk of cases. So it’s a pseudo-rent control.
I’m not saying something is right or wrong, just saying everything has multiple layers of problems.
Nah, watch this if you have time: https://www.youtube.com/watch?v=kpK5HiCKfgU
At least watch this money shot: https://youtu.be/kpK5HiCKfgU?si=YNQBxsn15NxGdQQ0&t=272 (wait for the video to reveal the construction years)
As Max Fisher puts it: American cities have been frozen in amber.
There is also a completely unreasonable shortage of water for a much bigger city.
I've lived on the westside of LA for ~20 years, so one secret I like to let people in on: there's no water shortage. There's a literal ocean of it. I can see it right out my window.
And all that it takes to turn seawater into potable freshwater is energy.
We don't have a water problem. We have an energy problem.
For all of LA County, it would take 500–750 MW each year to use seawater for all our freshwater needs.
Or put another, with a single nuclear power plant, we would solve all LA's freshwater needs -- forever.
You don't have an energy problem, you have a political problem. Fresh water is wasted on thirsty plants destined for agriculture (like alfalfa), by rich farmers who inherited water rights put into law ages ago. It's very simple to solve water usage in California, it just requires a governor that has a tiny amount of grit and cuts into their water rights.
It's crazy how to some, building a whole nuclear reactor and dozens of desalination plants seems like a simpler solution than making a couple of very wealthy farmers a bit angry for a while. Capital really is all-powerful in the States, it even holds power in the very minds of its citizens.
This is more like the construction date of buildings that have survived. Some early neighborhoods (like palms) have been completely replaced building by building so they really appear as dark here when they weren't. It had a downtown in the 1890s but all those buildings are gone. https://en.wikipedia.org/wiki/Palms,_Los_Angeles#/media/File...
it's basically this data: https://portal.assessor.lacounty.gov/ through this portal https://data.lacity.org/
Exactly this -- This is more like the construction date of buildings that have survived. Everything demolished, burned, or replaced is invisible.
Probably should put that front and center.
Los Angeles had the largest public transportation network in the United States until we paved over it[1]. We had over 1,300 miles! You could've gone from Huntington Beach to Downtown and all the way up to Burbank. You can see many of the maps of Los Angeles at the public library[2]. I don't live there anymore, love that place though.
[1] - https://www.pbssocal.org/shows/lost-la/from-rail-to-roads-an...
[2] - https://www.lapl.org/research-guides/maps/maps-los-angeles
My mom (who is 97) has a vivid memory of seeing FDR in 1935 -- the whole extended family took the the Red Car from Compton to downtown to see his motorcade. She remembered the electric trams worked really well, especially for folks without much money.
> worked really well, especially for folks without much money
That's probably part of the reason they got rid of them. You still see that argument used against transit: "it will bring _____ to our part of town".
Bit misleading since it only shows properties still standing, seemingly. So the older periods look extremely empty.
This is one of those 'hey, I can vibe code this in a weekend' projects. Just look at how the AI decided to the entire map in dark mode, making it nearly impossible to tell the ocean and the land apart.
Yes, great point. What was torn down, burned, destroyed, etc. along the way isn't here. This is the surviving city, not the city as it was.
A complementary view of one point in time is the LA Noire video game's attempt to recreate a (condensed and simplified) 1940s LA environment, with 3D architecture, cars, and ongoing expansion.
https://www.youtube.com/watch?v=OGPh2AcmG2A
The storytelling atmosphere is somber film-noire-ish, but there's simultaneously a feeling of national prosperity and potential for many (with notable unjust exceptions), like I think fewer people feel in more recent decades.
Would also be interesting to try to convey that kind of change over time, in an immersive way.
Did not think of that - yes that is a really interesting idea. Totally different way with interacting with data. I'm going to ponder that...
Interesting visualization. I feel like it's misleading though because the presentation shows only Los Angeles City boundaries, not the area in general. LA City has that strange vertical shaft down the the port so the city could keep the taxes from the port, but the visualization shows the rest of the area as empty, which of course it is not. It also excludes Orange County, Riverside County, and the whole area north, the San Fernando Valley, and those all arguably are just as important to the story. In the end, I think the visualization ends up being a net negative in it's current form since it's very misleading
Having moved to LA this february, the sprawl is really something I had no true appreciation for until I moved here for real, and tried to run errands across town. It's a gigantic, beautiful, complicated place.
One the experiences for me that never gets old is coming in to LAX (flight path East to West) and the sprawl just goes on forever. The other crazy thing that 60% of the population speak a language other than English at home. So I think it has one of the best options for cuisine in the world, because it's all there (somewhere!)
The density at least means you don't have to really run across town for much and can stay within a certain radius for most all your needs and wants. I mean look at the density of costcos alone. Many other metros might have 1 or 2 for the entire area. Then again a lot of other metros you basically can drive end to end in 25 miles.
I'm confused. LA doesn't strike me as dense. How dense can you get with huge areas of single family homes?
LA is the densest major urban area in the country. The MSA isn't dense cause it includes all of Los Angeles County which is half desert and mountains. But the built up area beats Chicago and New York cause it has consistent, medium suburban density, 7400 people per sq mi. The others have dense city, New York City is 29,000 people per sq mi, but the far suburbs drop off.
8200/sqmi on average. Even the single family home areas punch above their weight compared to the rest of the country because lots are mostly only 50ft wide and most all build-able land is put to some sort of use already.
It's a bunch of cats (mid-sized, and generally mid all-around, cities) fighting under a blanket. The history of the place is a reaction against New York, where the city is dense and had a bunch of super tall buildings. LA, as a region, said "well we don't want that and enacted a bunch of building codes to hamstring any single city in the region from potentially being a successful, mature urban center.
Pretty infuriating to visit Barcelona recently and see that there was a perfect example of good urban planning sitting right there for decades that LA could've simply copied. In the long run this region is simply incapable of maintaining its infrastructure with its tax base, even today you can see it starting to collapse.
I did a project recently where I extracted every Los Angeles building permit record for a property and was able to look at the evolution of its infrastructure and tenancy over time by embedding the permit documents into an image-based embedding model. Could be an interesting way to incorporate more granularity of the history of properties over time, although it dramatically increases the scope of data processed.
Interesting idea. Is there a practical way to obtain those permit records at scale?
I had an LLM reverse engineer the API protocol of LADBS and extract the content I wanted. Wether that scales from one property to many (rate limits for one) I don't know, but I didn't encounter anything in the thousands I extracted.
I noticed most of the tall buildings are sixties to eighties. Some more info about that here. https://www.pbssocal.org/shows/artbound/a-brief-history-of-l...
Thank you! Great link!
And here is one that is just fun to watch because of Huell Howser --
Tallest Building | Visiting with Huell Howser https://www.youtube.com/watch?v=5ziEDhCPjOQ
Wikipedia has a nice visualization of the history of LA's tallest buildings.
https://en.wikipedia.org/wiki/List_of_tallest_buildings_in_L...
They paved paradise, and put up a parking lot.
Paradise? LA was a big giant horrible underdeveloped wasteland in Spanish/Mexican times which, at the time in 1849, had 1,600 residents. Most of them had a largely pastoral life and life was brutal there.
LA under US rule is the prime example of what industrialized people can do to a place that lacked nearly everything of what it is at this moment: a world-class city.
Objectively, if it had stayed under Mexican rule, it’d resemble Yuma at best or Tecate at worst. I should know, my family lineage goes back to that era to both sides of the border.
One's "underdeveloped wasteland" is someone else's untouched paradise. Particularly someone like Joni Mitchell.
Was it that a big, giant, horrible wasteland because it was undeveloped? That is, was there something bad about it other than being undeveloped? Personally, I love living in the city AND land in its natural state.
Also, GP was quoting a song lyric.
I think the best intro to LA is Cadillac Desert by Marc Reisner (it's really about the entire West and its relationship to water, but I think the first few chapters explain LA better than many other books.)
It's part of a very popular song from the 70s by Joni Mitchell called "Big Yellow Taxi".
Counting Crows did a cover in 2002.
Is there an alternative if 13 million people want to live somewhere?
Somewhat sadly, the reason a lot of the ancestors of those 13 millions moved there was that they wanted an unpaved paradise.
Unfortunately, humans do not know restraint.
Wow this is inspiring. I would love to see a very similar visualization for Stockholm, Sweden. I think there is a beauty in seeing a summarized history of expansion, and in reality I can't help but think this is a very fast population boom. One I am sure most metro areas would struggle with. Makes a lot of criticism of LA planning in hindsight feel very unfair.
Nice! Would be better if it shows the difference between the ocean and other land
Agree, I personally also think dark mode never goes well with a map-based app...
Especially with this sort of map regarding this specific city. For example, Beverly Hills is a separate municipality contained entirely within the borders of Los Angeles. It appears here like an empty black space no different from the ocean, lakes, mountains, and parks also scattered around the city. The styling of this map makes it impossible to tell if an area is truly undeveloped and if so, why. Throw in the way there appears to be arbitrary selection criteria for some buildings outside city limits that make them appear as lone buildings in undeveloped space, and I think it adds up to potentially give people a wrong picture of the area.
Yes, good point. The LA City data was rich, but the other communities have data in other places. I will see what I can do.
Great, I'm sure getting more data for a complete picture of the area is a huge undertaking, but simply switching to the light map that shows the geography more clearly is a big improvement.
the Wilshire Corridor view is completely wrong, it should be the stretch of tall buildings a bit above Century City in the Century City view.
What is that huge gap near Venice?
This is super cool. Seems to be quite laggy for me though, when the timeline reached 2026 and stopped, buildings still kept popping in for the next 30 seconds.
Yep, that was my misconfiguration of the CloudFlare cache. Hopefully fixed now.
The obvious next step here is to do LA county, since so much sits outside the city limits.
Is this actually representing homeless encampments?
Very cool, but I think it'd be even better if the new buildings popped up rather than faded in.
SF version would be quite boring
Well done! What an illustration of the amazing spirit of the founders, followed by the glacial movement as we allowed NIMBYs to take control through more and more laws.
Brilliant.
wild to see that, reminds me vaguely of the amazing ariel photos by kite of San Francisco after the earthquakes in 1906
* https://en.wikipedia.org/wiki/File:San_Francisco_in_ruin_edi...
early 1900s to early 2000s was a wild and crazy ride for humanity
when I was a teenager I used to run early morning before sunrise and I would never see a car, like maybe once per hour
but these days it's like rush hour at 5am which is frustrating and annoying
and then I realized in perspective that within my own lifetime from teen to 60 the world population has more than DOUBLED, so what I am experiencing makes some sense in that regard (plus technology advancement)
hey I feel like we should work together on something. I maintain https://www.kaggle.com/datasets/landrecordsus/us-parcel-laye... and https://landstats.com.
Now do Austin?
I joined the county's 2020 lidar building footprints (LARIAC) to the assessor roll, so every one of the 1,129,558 buildings inside the City of LA has a footprint, a height, and a year built for 98% of them. (All public info, but kind of a pain to grab.)
The page extrudes them in 3D and plays the city filling in from 1880 to now. Colors are by decade, or switch to height and fly to downtown. Hover any building for its address, year, height, and footprint. Some things I found: the 1950s, not the 1920s, is the biggest decade still standing; the Valley visibly snaps into existence after the war; and downtown's 150-foot height limit shows up as a hard ceiling until 1957. Zoomed out it draws a 100 m grid because a citywide view can't carry a million polygons, and heights are exaggerated below street level zoom (the corner label says by how much).
Stack: DuckDB spatial for the join, tippecanoe to PMTiles, MapLibre fill-extrusion, all static files on R2 with no server. City of LA only, since the parcel polygons I pulled stop at the city line.
Happy to answer questions about the data or the rendering.
[Just a fun project, no commercial relevance.]
Didn't realize you could zoom in until I saw this. It looks really cool when you zoom in and it replaces the boxes with actual building shapes.
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Yey yet another vibe coded viz. these are the “hello world” of LLM projects.
nifty. what about this makes it HN worth? What cool problems did you (not the robot) solve? What did you do beyond prompting it, is there anything for others to learn from? Was the data difficult to acquire, clean up, or is this just an obvious viz on a public dataset anyone could get? Did you glean insights from having this viz, does the graphic serve a narrative or distilling information not otherwise apparent, or is it just pretty?
I ask these genuinely. It’s the difference between “oh I figured out how to print ‘hello world’” vs “I built something”
If you want to encourage folks to continue their efforts and really "build something", I think you'd want to ask your questions in a way that shows genuine interest and support, rather than ridiculing and questioning the level of effort involved.
I agree, I'd love to learn where the dada was sourced! I'm also curious why it appears to come in waves, as opposed to each building going up independently (as I would have expected it to in reality). Cool idea! I can see my house from here haha.
The waves are partly real and partly me.
LA genuinely built in bursts. The 1920s and the postwar decade each account for over 230,000 buildings still standing, and the 1930s and 1970s onward are much thinner, so even a perfect per-year animation would surge and pause.
But really it's for performance -- I group buildings into 5-year bins and fade each bin in over its span, rather than popping each building at its exact year.
A per-year filter on a million polygons re-tessellates every visible tile, which was too slow to animate, whereas fading pre-built layers is reasonably fast.
Glad you found your house!
This started as a data puzzle. There is a lot of public data but it's hosted by for-profit companies and the data models don't seem to be coherent (probably lots of good reasons for the data models being the way they are, so no criticism, and it's wonderful they are public.)
So for LA City, they use Socrata (owned by Tyler Technologies -- NYSE: TYL) to host and publish open data. LA City also uses Esri's ArcGIS for geo-based data.
So behind the scenes there is my code that builds a parquet database of * MyLA311 service requests * Permits * Construction Enforcement * Crime * Parcels Id with Polygons * Lidar
So that part was a typical data-munging exercise, and it was fun & interesting to me to learn how public entities try and deal with IT budget cuts and service the community, etc. (For example, 311 requests for homeless issues are transferred to another department, so they all look they are closed immediately, but I never could find the agency data that ultimately resolved that type of request.)
So I have a pile of data that is organized in a way that makes sense to me, but I could not build an interface that I liked.
So I asked Claude to create a fly-over visualization to see what it could do with this data, and it blew my mind.
I'm a life-long coder and I'm old, so it's an interesting experience to see how good these models and coding harnesses are, and how quickly they are improving.
As to what makes this HN worthy? I enjoyed playing with the interface, and there might be more people than just me who love LA (warts and all) and its history and architecture. So it's interesting and I'm not asking for anything in return, so for me that satisfies the "HN Show" criteria.
The deeper question for me right now is what does hacking mean when the coding is done by these systems? It's a different kind of hacking, and its makes things possible that impossible before, but it's a million miles away from 6502 assembly.
It’s great! Agreed don’t feed the trolls.
I’ve helped with a few other zoning visualization projects recently, similar workflow. The only similarity is that each city/jurisdiction makes its data available in a different way. It’s usually accessible but it does mean there’s a lot of work munging the data to a usable format.
Here’s one of the projects: https://github.com/kfarr/zoningviz
Yes, this is incredibly similar to the pipeline I ended up with -- https://github.com/kfarr/zoningviz/blob/main/HOW_IT_WORKS.md
The other thing I learned is that some of the data sets use a destructive insert, so unless someone is doing a data snapshot data elements can be lost. (The vendors charge extra time-series option.)
No need to justify yourself to some bitter, petty, sad troll. Let the upvotes and discussion speak for itself. I love seeing other people's vibe-coded projects come to life. I've re-started a bunch of stalled hobby projects thanks to AI.
> What cool problems did you (not the robot) solve?
Building products has nothing to do with technical problems, just the end result. This is in contrast with things like writing a library or coming up with a new algorithm, or doing research, or even writing a technical blog post, etc.
> or is it just pretty?
People have been sharing "just pretty" things on HN for decades. It might be interesting, thought-provoking, discussion-worthy, or whatever. Even if this wasn't vibe-coded, it wouldn't be some monumental technical achievement. Your point is absolutely moot.
Pretty great day for HN. You can’t just shut off people anymore with „machine did it, not you” as we live in new reality. Comments below make even more sound argument, for data viz we probably don’t need novel problem solving, just people interested to see viz
what have YOU built lately? what amazing incredible problems have YOU solved? yea quit raining on other people's parade and stfu
