This site from the Land Processes Distributed Active Archive Center presents Global Topographic Data (GTOPO30), a global digital elevation model (DEM) with a horizontal grid spacing of 30 arc seconds. GTOPO30 was derived from several raster and vector sources of topographic information and has been divided into tiles for easier distribution. Detailed information on the characteristics of GTOPO30 including the data distribution format, the data sources, production methods, accuracy, and hints for users, is found in the GTOPO30 README file. Please be sure to check the GTOPO30 Frequently Asked Questions for further information, or if you are having difficulties viewing the data.
