San Francisco 49ers
The team was founded in 1946 as a charter member of the All-America Football Conference (AAFC) and joined the NFL in 1949 when the leagues merged. The 49ers were the first major league professional sports franchise based in San Francisco. The name "49ers" comes from the prospectors who arrived in Northern California in the 1849 Gold Rush. The team is legally and corporately registered as the San Francisco Forty Niners. The team began play at Kezar Stadium in San Francisco before moving across town to Candlestick Park in 1970 and then to Levi's Stadium in Santa Clara in 2014.
49ers–Raiders rivalry
The 49ers–Raiders rivalry, more commonly known as the Battle of the Bay, is a professional American football rivalry between the National Football League (NFL)'s San Francisco 49ers and Oakland Raiders. This rivalry is unique in that both teams are members of different conferences within the NFL and have never met in a postseason game, making the rivalry purely geographic, as only 27 miles across San Francisco Bay separate Levi's Stadium, home of the 49ers, and Oakland-Alameda County Coliseum, home of the Raiders. The geographic aspect of the rivalry will end no later than 2020, when the Raiders relocate to Las Vegas, Nevada. Their 2018 Week 9 match up was their last true Battle of the Bay game barring any sudden changes to the NFL's schedule rotation.