This site has such a great concept behind it. It basically takes photos, from as far back as the 1840's, and imposes them on the current day sites through google maps. So a picture, any picture taken at anytime, can be posted onto the site (by anyone. Yes, you included!) and can be matched to the exact location that the photo was taken. You can also see any other Historypin photos and their stories that others leave. This is such a great tool to share photography, as well as history together in one great package.
Historypin is a digital time machine that creates a new way for the world to see and share history.
It was created by We Are What We Do, in partnership with Google.