Chris Olsen has used Esri Maps to create a series of interesting historical map interfaces for Toronto, Cleveland and Pittsburgh. The map for each city includes a timeline function that allows users to view historical maps of each city over the decades.
Toronto Historic Maps presents a series of historical maps of the Canadian city. The earliest map is the 1858 Boulton Atlas of the City of Toronto. The map also allows you to explore Goad fire insurance maps from 1880, 1889, 1913 & 1924 and includes maps from 1818, 1842 and aerial photographs from 1947.
Via: Recursion: Adventures from a Fractured Life
Cleveland Historic Maps features a number of historical maps from the Cleveland Public Library collection. My favorite in the collection is the 1852 Harris Blackmore map. You can also view historical Cleveland maps from 1874, 1881, 1898, 1912 and 1920.
Pittsburgh Historic Maps features a series of historic maps of Pittsburgh, dating back to 1835. The map also includes historical aerial photo maps from 1939, 1957 and 2005.
A number of markers on the map allow the user to learn more about historical landmarks in the city, using data from the National Registry of Historic Places and the Pittsburgh History & Landmarks Foundation.