St. Lawrence Island is located west of mainland Alaska in the Bering Sea, just south of the Bering Strait. The village of Gambell, located on the northwest cape of the island, is 50 nautical miles from the Chukchi Peninsula in the Russian Far East. The island is part of Alaska, but closer to Russia and Asia than to the Alaskan and North American mainland. St. Lawrence Island is thought to be one of the last exposed portions of the land bridge that once joined Asia with North America during the Pleistocene period. It is the sixth largest island in the United States and the 113th largest island in the world. It is considered part of the Bering Sea Volcanic Province. The Saint Lawrence Island shrew is a species of shrew endemic to St. Lawrence Island. The island is jointly owned by the predominantly Siberian Yupik villages of Gambell and Savoonga, the two main settlements on the island.

Beringia is defined today as the land and maritime area bounded on the west by the Lena River in Russia; on the east by the Mackenzie River in Canada; on the north by 72 degrees north latitude in the Chukchi Sea; and on the south by the tip of the Kamchatka Peninsula. It includes the Chukchi Sea, the Bering Sea, the Bering Strait, the Chukchi and Kamchatka Peninsulas in Russia as well as Alaska in the United States and the Yukon in Canada.