Mainsail Rock (60°37′S 46°3′W) is a rock lying 0.6 nautical miles (1.1 km) southwest of Spine Island in Sandefjord Bay, South Orkney Islands, Antarctica. It is the largest and easternmost of a chain of three rocks trending in a northwest–southeast direction off the southeast side of Monroe Island. The rock was named by Discovery Investigations personnel following their survey in 1933.
References
Mainsail Rock Wikipedia(Text) CC BY-SA