 Guesalaga Peninsula and Arturo Prat Base (in the foreground) from English Strait, with Fuerza Aérea Glacier and Breznik Heights in the background. | |
 Greenwich Island in the South Shetland Islands | |
  Guesalaga Peninsula Location on Antarctic Peninsula  Guesalaga Peninsula Location in Antarctica | |
| Geography | |
|---|---|
| Location | Antarctica |
| Coordinates | 62°28′45.3″S 59°40′00″W / 62.479250°S 59.66667°W |
| Archipelago | South Shetland Islands |
| Administration | |
| Administered under the Antarctic Treaty System | |
| Demographics | |
| Population | uninhabited |
Guesalaga Peninsula is a small, L-shaped, low-lying shingle covered peninsula on the east side of Discovery Bay, Greenwich Island in the South Shetland Islands, Antarctica forming the northwest coast of Iquique Cove and the north side of its entrance. The feature is projecting 700 m (766 yd) southwestwards and 300 m (328 yd) wide, with the narrow shingle Reyes Spit (62°28′46.3″S 59°40′29″W / 62.479528°S 59.67472°W) extending 400 m (437 yd) southwestwards from its west extremity Reyes Point (62°28′44″S 59°40′13.3″W / 62.47889°S 59.670361°W) into Discovery Bay. The Chilean Antarctic base Arturo Prat is situated on the peninsula.
Guesalaga Peninsula is named after Captain Federico Guesalaga, leader of the 1947 Chilean Antarctic Expedition in the frigate Iquique and the transport ship Angamos that established Arturo Prat Base, while Reyes Point and Reyes Spit are named after Navigation Second Sergeant Camilo who was in charge of navigation instruments in the Iquique.