Billown Circuit

Billown Circuit
LocationCastletown, Isle of Man
Time zoneGMT
Coordinates54°05′18″N 4°39′52″W / 54.08845°N 4.66455°W / 54.08845; -4.66455
Major eventsSouthern 100, Pre-TT Classic Races, National Road Races, Ultra-Lightweight TT, Lightweight TT
Length4.25 miles (6.84 km)
Turns14+
Race lap record2:12.735 115.267 mph (185.504 km/h) (Michael Dunlop, Suzuki, (2017))

The Billown Circuit is a motorcycle road-race course used for the Southern 100, the Pre-TT Classic races and the National Road Races meetings near Castletown on the Isle of Man. Racing is held on public roads closed for racing by an Act of Tynwald, the parliament of the Isle of Man.

The course is 4.25 miles (6.8 km) long and is in the parishes of Arbory and Malew. The course start-line is on the outskirts of Castletown and the course includes parts of the primary A5 New Castletown Road, the A28 Castletown to Ballabeg road, the A7 Ballasalla to Port Erin road and the A3 Castletown to Ramsey road.