"Welcome to the most comprehensive database of its kind in the world. It contains 66123 locations with over 29.433 name changes once, and 5,500 thrice. All locations are EAST of the Oder and Neisse rivers and are based on the borders of the eastern provinces in Spring 1918. Included in this database are the following provinces: Eastprussia, including Memel, Westprussia, Brandenburg, Posen, Pomerania, and Silesia."