Over 40,000 vintage photos of New York City from the New York Public Library archives have been geotagged to a Google Map, letting you click right through history on every street corner.
OldNYC is the baby of software engineer Dan Vanderkam, who worked on a similar project when he lived in San Francisco (yep, OldSF). Since 2013 Vanderkam has been collaborating with the NYPL staff, where volunteers have been uploading and geotagging photos, then scanning in relevant caption information using optical recognition software. The best part is that it's all editable by the public if someone wants to make an annotation or correction.
"My hope is that users will leave their own anecdotes about the photos and improve the quality of data on the site, by flagging inaccuracies and typos," Vanderkam tells CityLab.
Each dot on the map opens a spread of photos taken at or around that very spot at various points in history. You can peruse the thumbnail previews or head on over to the NYPL site for the original high-res images.
For example, the dot at Herald Square links up to this 1927 gem of the elevated train that once ran through the city:
But you could also sift through the photos to find the very same train being constructed in 1909:
Where it really gets awesome, though, is when you switch to Street View on the map. The dots at each intersection are clearly visible, even in Street View, so you're able to make some awesome side-by-side comparisons of New York City now and then.
I clicked up to Times Square for a current day image:
Then found this awesome 1916 photo of the same intersection, totally unrecognisable:
Like I said, grab a beer and get comfortable because it's hard to look away. And let us know what gems you uncover.