There are also footprint layers, which merely indicate the extents of the corresponding county's photography (plus they're color coded as to the layer license see above), and there are occasional metadata layers. A given WMS might have multiple layers covering the same region where the layers differ in the age or resolution of the photographs. The layer names also indicate the year in which the photos were taken. The photos are generally separated by county, though not all counties are present for all states, and some counties are further split into multiple layers. The WMS capability URLs are available from the USGS's Seamless server's WMS Access List. The GeoTIFF can be split into TMS-style tiles using GDAL2Tiles, and then used in JOSM or Potlatch.
If the footprint is colored blue, the data is public domain, while the footprints for restricted data are colored yellow. If it's not listed as public domain, it can't be used.Īlternately, the WMS for each state includes footprint layers as well as image layers for each county. You can check the license for a county's imagery at the USGS's Orthoimagery List.
The data is generally available on a county-by-county basis.