Solving Real Estate Mysteries: Historical Aerials (No. 1 of an occasional series)

Let's say you need to figure out (i) how to interpret a legal description that refers to property owners of several decades ago, or (ii) when a stream was piped under a property. A good resource is Historic Aerials (while not all of their aerials are historic, they certainly all are historical).

In the first case, I found only one relevant historical aerial photograph of the site in question, but it was enough to answer my question. In the second case, I found aerials from 1931, 1946, 1959, 1968, 1980, 1988, 2000, 2002, and 2005, and I found the answer I was looking for by comparing the 1946 aerial with the 1959 aerial (i.e., the stream that flowed across the property in 1931 and 1946 disappeared beneath a building in 1959).

Another great resource, particularly in the Delaware Valley, is the "Live Map" feature created by Ben Ruset at his and Guy Thompson's fantastic website njpinebarrens.com. The Live Map begins with a Google Map interface (i.e., you can view a road map, a satellite aerial, or terrain view) and adds on historical aerials views from 1930, 1995, 2002, 2006, and 2007 (not sure how far they go beyond New Jersey, but I've been able to view many of them well into Pennsyvlania and Delaware), topo, historical topo, and USGS Digital Orthoquadrangle ("DOQ").