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Stratoscopelast Tuesday at 6:55 PM1 replyview on HN

USGS has this on their topoview site:

https://ngmdb.usgs.gov/topoview/viewer/

Pick the area you want to look at, select a historical topo map, and click the Show button. Then you can use the Transparency slider to see the topo map overlaid on a current street map.

You can discover some interesting things this way. For example, I used to live on Hawthorne Avenue in Palo Alto (CA). The 1897 topo map shows that this street was originally a railroad spur line off the main Southern Pacific track (now used by Caltrain and freight). This spur line turned left onto what is now Middlefield and then turned right to serve the Catholic University (now St. Patrick's Seminary).


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ProllyInfamouslast Tuesday at 11:46 PM

Thanks for occupying my past few hours (great USGS link!).

It's crazy to me how many errors are on these official maps (even in to present day, e.g.: roads that don't actually exist), particularly the newer maps creating connections between roadways which don't actually exist (I imagine this is image-recognition errors, when former human techs used to actually field verify everything).

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