The Maidenhead Locator System is a system for locating positions on the globe commonly used by amateur radio enthusiasts or "hams". It is named after Maidenhead, the town outside London where it was first conceived by a meeting of European VHF managers in 1980. A Maidenhead grid square measures 1° latitude by 2° longitude and measures about 70 × 100 miles (113 by 160 km) in the continental USA. The American Radio Relay League uses the six digit form of the Maidenhead Locator System for its 10 GHz contest.
