East Base on Stonington Island is the oldest American research station in Antarctica, having been commissioned by Franklin D. Roosevelt in 1939. The station was built as part of two US wintering expeditions – United States Antarctic Service Expedition (1939–1941) and Ronne Antarctic Research Expedition (1947–1948). The base covers 1,000 metres (3,300 ft) from north to south and 500 metres (1,600 ft) from east to west. The base was accorded the status of one of the Historic Sites and Monuments in Antarctica on 7 May 2004.