Would you like a more graphic representation of the building where you or  
your ancestors lived in New York City?

http://gis.nyc.gov/doitt/nycitymap

The above URL is the NYC government site where you key in a specific 
address and the result is a map of the area showing an outline of every building.

After locating a building, click "Show Additional Information" and data 
will be provided such as lot frontage, depth and area; year built; gross floor 
area; number of residential units; and whether it has been designated as a 
Landmark building. 

Also, if you click on the (non-intuitive) camera icon you get a slider with 
years on it, and get aerial photos taken in those years.


Source:
http://www.avotaynu.com/nu/V11N09.htm



I hope this information is useful or, at least, interesting.

Happy Shavuot*,

Walter Greenspan
Great Falls, MT & Jericho, NY

* The 2-day Jewish Biblical Festival of Shavuot (shuh-VOO-oht) commemorates 
the day when G-d gave the Jewish people the Torah (the Five Books of Moses) 
following Moses' descent from Mount Sinai in 1310 BCE, begins 7 weeks from 
the second Seder of the Jewish Biblical Festival of Pesach (Passover), which 
this year will be at sundown on Tuesday, May 18 on the civil calendar.
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