Why does my orthoimagery search on The National Map return multiple tiles for downloading?
Orthoimagery is usually very large in file size, so we stage the data in "tiles" that can be reasonably transported over the Internet. Orthoimagery from the National Agriculture Imagery Program (NAIP) that is distributed via The National Map Data Download is in compressed 10:1, JPEG2000 format in 3.75 minute x 3.75 minute tile extents.
A larger catalog of orthoimagery can also be downloaded using EarthExplorer.
Learn more: USGS National Geospatial Program: Imagery