Natural Earth is a public domain map dataset available at 1:10m, 1:50m, and 1:110 million scales. It includes both cultural and physical layers. Featuring tightly integrated vector and raster data, with Natural Earth you can make a variety of visually pleasing, well-crafted maps with cartography or GIS software. Natural Earth was built through a collaboration of many volunteers and is supported by NACIS (North American Cartographic Information Society), and is free for use in any type of project (see our Terms of Use page for more information).
地址：http://www.naturalearthdata.com/