The Library of Congress has an online exhibition of a Russian photographer named Sergei Mikhailovich Prokudin-Gorskii called The Empire That Was Russia.
In the early 1900s Prokudin-Gorskii formulated an ambitious plan for a photographic survey of the Russian Empire that won the support of Tsar Nicholas II. Between 1909-1912, and again in 1915, he completed surveys of eleven regions, traveling in a specially equipped railroad car provided by the Ministry of Transportation.
The interesting thing about him is that he invented a way to take color photographs. He would quickly take three black and white pictures using red, green, and blue filters on glass plate negatives. Then using a projector fitted with the same filters he could project the image in color.
The Library of Congress purchased the slides from his heirs, and created digital pictures from them. These pictures are just amazing.