Many of us are familiar with free USGS Digital Orthorectified Quarter Quadrangles (DOQQs) that cover the US in a combination of color and black-white high resolution imagery. In many cases, this is the oldest data you can find for free; and in many very rural locations, it might be the only data you can find – new or old! What can be a challenge with DOQQ data is locating the name(s) of the quad you want to download. Esri offers a free polygon shapefile that will tell you DOQQ names, but not everyone has access to ArcGIS. And even for those with ArcGIS, the attributes that are included with the free USGS DOQQ layer are scant at best.
Well, look no farther, as the USGS has a well attributed DOQQ shapefile that can be downloaded from this site for free. There are three versions of the DOQQ shapefile for 1:24,000, 1:100,000 and 1:250,000 quads. Embedded in the 1:24,000 shapefile is the name of each quad as you move up to the 1:100,000 and then the 1:250,000 layer – this information is lacking in the free Esri version.
Happy downloads and hunts for free DOQQ raster data!
Brock Adam McCarty