Introduced in Google Earth 5 a few years ago, historical imagery remains one of the neatest features of Google Earth that many people don’t know about it. In the time since the initial historical imagery release, Google has updated quite often with additional imagery. Much of the “new” imagery is fairly recent, though we’ve seen a few major historical additions such as the huge batch of imagery from London in 1945 a few years ago.
Recently, thanks to the work of aerial photographer Harrison Ryker decades ago, Google has released an amazing collection of historical imagery in San Francisco from 1938.
The imagery was captured by a group of pilots that made a variety of north-to-south runs across the city, ultimately helping to create 164 large prints of the city. Because they were relatively low to the ground, the resulting imagery is amazingly sharp (roughly 1 meter resolution), considering it was captured more than 70 years ago!
To see it for yourself, simply fly over to San Francisco and slide the historical imagery tool back to 1938. You can also load up this KML file, which should take care of both steps for you.
(via Google Lat Long blog)