Aerial Photo (technically, a Digital Orthophoto Quadrangle) of UTM Zone 10.
See the file "Continental U.S. UTM zones" for the area of the US covered by
zone 10.

A digital orthophoto quadrangle (DOQ) is a computer-generated image of an 
aerial photograph. It has been orthorectified -- altered so that it has the 
geometric properties of a map. This process also enables accurate 
measurements of ground distance on the photos -- just as you get on maps -- 
and ensures that the photos can be used in automated mapping and geographical 
analysis software along with other digital cartographic data.

The images are served by TerraServer, a cooperative research project between 
Microsoft and the USGS: http://terraserver.microsoft.com
