Amsterdam, Barcelona, Boston, Chicago, Florence,
Ireland, London, Madrid/Spain, Lower, Midtown, & Upper Manhattan, Paris, Philadelphia, Rome,
San Francisco, Scotland, Seattle, Venice, Washington, DC

The best known USGS maps are those of the 7.5-minute, 1:24,000-scale quadrangle series. A scale of 1:25,000 is used for maps based on metric units (1 centimeter = 0.25 kilometer). The area portrayed on each sheet ranges from 64 square miles at latitude 30 degrees north to 49 square miles at latitude 49 degrees north.