Oxford are back...
Not just speedway, though. Taking the First Division clubs in 1965-66, we have lost Filbert Street, White Hart Lane, Boleyn Ground, Highbury, Roker Park, and County Ground. In Division 2, we have lost Maine Rd, The Dell, Highfield Rd, Leeds Rd, Millmoor, Baseball Ground, Burnden Park, Gigg Lane, Ninian Park, and Ayresome Park.
It's called "progress" (or so they claim).