miles inland from the original 1946 airstrip and across the bay from the historical Thule settlement, to which it is connected by an ice road. The joint Danish-American defense area, designated by treaty, also occupies considerable inland territory in addition to the air base itself. World War II After the German occupation of Denmark on 9 April 1940, Henrik Kauffmann, Danish Ambassador to the United States, made an agreement "In the name of the king" with the United States, authorizing the United States to defend the Danish colonies on Greenland from German aggression – this agreement faced Kauffmann with a charge of high treason by the protectorate Government. The first US-sponsored installations at Thule were established after the US Secretary of State Cordell Hull and the defected Danish Minister to the United States Henrik Kauffmann signed The Agreement relating to the Defense of Greenland in Washington, D.C. on the symbolically chosen date of 9 April 1941. The treaty, denounced by the Danish government, allowed the United States to operate military bases in Greenland "for as long as there is agreement" that the threat to North America existed. Beginning in the summer of 1941, the US Coast Guard and the War Department established weather and radio stations at Narsarsuaq Airport (Bluie West-1), Sondrestrom Air Base (Bluie West-8), Ikateq (Bluie East Two), and Gronnedal (Bluie West-9). In 1943 the Army Air Forces set up weather stations Scoresbysund (Bluie East-3) on the east coast around the southern tip of Greenland, and Thule (Bluie West-6) to be operated by Danish personnel. Many other sites were set up, but BW-6, isolated in the far North, was then of very minor importance. Joint weather station After liberation, Denmark ratified the Kauffmann treaty but began efforts to take over US installations. Nonetheless, in summer 1946, the radio and weather station was enhanced with a gravel airstrip and an upper-air (balloon) observatory. This was part of an American-Canadian initiative to construct joint weather stations in the High Arctic. This station was under joint US-Danish operation. The location changed from the civilian village at Thule (Dundas) to mainland Pittufik. In 1946–1951, the airstrip played an important role in Arctic resupply, aerial mapping, research, and search-and rescue. The ratification of the treaty in 1951 did not change much, except that the Danish national flag must be side by side with the US national flag on the base. Modern air base