The Denver Broncos are a professional American football team based in Denver, Colorado. They are members of the West Division of the American Football Conference in the National Football League. The Broncos began play in 1960 as a charter member of the American Football League and joined the NFL as part of the AFL-NFL merger of 1970. The Denver Broncos have three AFC West rivals - the Kansas City Chiefs, Oakland Raiders, and San Diego Chargers. Aside from the aforementioned AFC West teams, the Broncos have had intra-conference rivalries over the years with the Cleveland Browns, Pittsburgh Steelers, and New England Patriots.