TOPO! Software includes 5 map layers: 2 national Geographic atlas layers, 1:500,000 scale USGS regional maps, 1:100,000 scale USGS topographic maps,& 1:24,000 scale (7.5') USGS topographic quads - the most detailed topographical maps available.
Computer system requirements: Windows 95, 98, 2000, ME, NT & XP. Mac OS 9.0 or above, or OS 10.2 or above.
