One web site should interest any genealogist or historian. WhatWasThere.com has a simple purpose: provide a platform where anyone can easily upload a photograph with two straightforward tags to provide context: Location and Year. If enough people upload enough photographs in enough places, together we will weave together a photographic history of the world.
What Was There encourages everyone to upload old photographs of any place in the world. Visitors to the website can view these photographs by browsing to different locations on a map. You can see what different sections of your native city or any other place in the world used to look like. With each photograph there are details that you can view to obtain further information. Amongst other things, these details include the year the photo was taken. Sections of the photographs can be magnified to get a better look at those old photos.
I tried looking for a few smaller towns on WhatWasThere.com but was generally unsuccessful. To be sure, there are many photos taken in small towns but not in every town. However, I was able to look at many cities of the past, some as early as the 1890s. I noticed that many of the photos came from the Library of Congress although I also saw other sources as well.
You can check out WhatWasThere at http://www.whatwasthere.com/
Note: The above picture is of the Park Street Station subway entrance on Boston Common in Boston, Massachusetts, taken in 1900. Surprisingly, the place hasn't changed much in 111 years. However, please note the fashions of the people in the picture. You can click on the image above to see a larger picture.