ATDI provides the ICS Map Server package that allows import and export of SDTS DEMs, re-projection, tiling, and generic functions for handling DEMs, Images and Land Cover files. ATDI’s interface allows users to enter a central coordinate and immediately retrieve the selected quadrangles. ATDI’s partnership with the USGS allows us to provide SDTS DEMs covering the entire USA for FREE – ATDI is a USGS business partner