Nelson Strait is the 9 km long and 9.8 km wide strait lying between Robert Island and Nelson Island in the South Shetland Islands, Antarctica. The strait was explored by early 19th century sealers and first charted by Nathaniel Palmer in 1821. While it had a variety of different names in the past (‘Harmony Strait’, ‘King George’s Strait’, ‘Parry’s Straits’, Davis's Straits’, ‘Détroit de Clothier’ etc.), the present name — probably taken from the adjacent Nelson Island — has become well established in international usage.