and largely barren. Eleven peaks rise to over high, their slopes furrowed with deep gorges filled with glaciers; the largest is Fortuna Glacier. The highest peak is Mount Paget in the Allardyce Range at . Geologically, the island consists of gneiss and argillaceous schists with occasional tuffs and other sedimentary layers from which fossils have been recovered. The island is a fragment of some greater land-mass now vanished and was probably a former extension of the Andean system. Smaller islands and islets off the coast of South Georgia Island include: Annenkov Island Bird Island Cooper Island Grass Island Jomfruene Pickersgill Islands Trinity Island Welcome Islands Willis Islands These remote rocks are also considered part of the South Georgia Group: Shag Rocks, west-northwest of South Georgia Island Black Rock, west-northwest of South Georgia Island Clerke Rocks, east-southeast of South Georgia Island South Sandwich Islands The South Sandwich Islands () comprise 11 mostly volcanic islands (excluding tiny satellite islands and offshore rocks), with some active volcanoes. They form an island arc running north–south in the region 56°18'–59°27'S, 26°23'–28°08'W, between about southeast of South Georgia. The archipelago comprises Candlemas, Vindication, Saunders, Montagu, Bristol, Bellingshausen, Cook and Thule discovered by Cook, and t The northernmost of the South Sandwich Islands form the Traversay Islands and Candlemas Islands groups, while the southernmost make up Southern Thule. The three largest islandsSaunders, Montagu, and Bristollie between the two. The islands' highest point is Mount Belinda () on Montagu Island. The fourth highest peak, Mount Michael () on Saunders Island has a persistent lava lake, known to occur at only eight volcanoes in the world. The South Sandwich Islands are uninhabited, though a permanently staffed Argentine research station was located on Thule Island from 1976 to 1982. Automatic weather stations are on Thule Island and Zavodovski. To the northwest of Zavodovski Island is the Protector Shoal, a submarine volcano. Extreme points Northernmost point – Cape North Southernmost point – on Cook Island Westernmost point – on Main Island (of the Willis Islands) Easternmost point – on Montagu Island Highest point – Mount Paget: 2,934 m Lowest point – Atlantic Ocean: 0 Climate The climate is classified as polar, and the weather is highly variable and harsh, making a tundra (ET) in Köppen climate classification. Typical daily maximum temperatures in South Georgia at sea level are around in winter (August) and in summer (January). Winter minimum temperatures are typically