The South Tasman Rise is an area of seafloor that lies 550 km south of Hobart, Tasmania in the Southern Ocean where water depths are about 1,500 metres. The South Tasman Rise is also known as the Tasmania Ridge or South Tasmania Ridge. The South Tasman Rise is a sunken landbridge that used to connect Tasmania to Antarctica.
Exploration of this oceanic region has taken place via sonar, gravity field, magnetic field, a few drill holes and deliberate or accidental dredging of rocks up to the surface.