USGS Topographic Map v2
This map presents land cover and detailed topographic maps for the United States. The map includes the National Park Service (NPS) Natural Earth physical map at 1.24km per pixel for the world at small scales, i-cubed eTOPO 1:250,000-scale maps for the contiguous United States at medium scales, and National Geographic TOPO! 1:100,000 and 1:24,000-scale maps (1:250,000 and 1:63,000 in Alaska) for the United States at large scales. The TOPO! maps are seamless, scanned images of United States Geological Survey (USGS) paper topographic maps.
Originator: USGS, National Geographic, i-cubed, National Park Service (NPS)
WMTS only, no WMS. USGS Providing it - sounds like only need to show copyright info. Download originals from : http://nationalmap.gov/historical/
Format: AGS, WMTS