Seymour Island is an island in the chain of 16 major islands around the tip of the
Graham Land on the
Antarctic Peninsula. Graham Land is the closest part of Antarctica to South America. It lies within the section of the island chain that resides off the west side of the peninsula's northernmost tip. Within that section, it lies slightly to the north of
Snow Hill Island and just east of the larger key,
James Ross Island, and its smaller, neighboring island,
Vega Island.