Tribal Nations Reservation Boundaries were digitized from the U.S. Geological Survey (USGS) 1:250,000 scale maps adjusted to be coincident with the Bureau of Land Management's Geographic Coordinate Database (GCDB) or the USGS 1:24,000 scale Digital Raster Graphics (DRGs). Where reservation boundaries are coincident with public land survey lines, they were copied from the BLM's GCDB. If boundaries were not coincident with GCDB lines, they were digitized on screen from the USGS DRGs. Reservation Boundaries will change as the GCDB is adjusted by the BLM and those data are imported into the Montana Cadastral Data Model. Montana Reservation Boundaries coincident with the BLM's GCDB or the USGS 1:24,000 scale Raster Graphics.