Ok guy's letting the cat out of the bag here this is by far the best free sight out there for doing your research and finding old towns or schools for metal detecting. Been using it for about 2 years now and have not seen any discussions about it so I thought I would share it with you all. I have found lot's of schools that don't exist anymore. http://worldwind.arc.nasa.gov/ It will show all the details thru the USGS black and white maps. Be advise the download is huge but well worth it. Let me know what you think? Matt