Free Library of Philadelphia
1.  How can I find out the age of my house?
By looking through various historic city atlases and aerial photographs in the Map Collection, the construction date of a house can usually be determined within a ten or fifteen year time span.
2.  Do you have U.S. Geological Survey topographic maps?
The Map Collection is a depository for U.S.G.S. topographic maps for all states, Puerto Rico and the U.S. Virgin Islands
3.  Do you have Sanborn Maps?
The Map Collection maintains historical Sanborn mapping for Pennsylvania, New Jersey, Maryland and Delaware. Sanborn mapping for Philadelphia is historical and current
4.  What are the boundaries of my neighborhood?

Because neighborhoods are not defined by ordinace, boundary streets are open to debate. The Map Collection uses various historical sources to identify specific neighborhoods and deliniate boundaries

5.  How do I find names of estates on the Main Line?
The Map Collection has a series of Main Line railroad atlases, from the 1880s to the 1980s, that indicate land holdings and estate names