The Bay to Birdwood is an annual historic vehicle run held in South Australia. The special 40th anniversary 2020 Bay to Birdwood took place on 27 September 2020 and involved antique, veteran, vintage and post-war/early-classic, classic, post-classic and modern vehicles: an event celebrating every decade of historic motoring.

The Bay to Birdwood is one of the world’s great historic motoring events. First held in 1980 the event has become a fixture on the South Australian events calendar. It is a mass-participatory citizen-collector historic motoring event that draws participants from far and wide and regularly attracts thousands of spectators to line the route and attend the start and finish events.