Part of the Kingdom of Denmark, Greenland observes Summer Time simultaneously with Europe. Summer Time thus begins at 00:00 East Greenland Time on Sunday, and 22:00 West Greenland Time on Saturday, and ends at 01:00 EGST on Sunday and 23:00 WGST on Saturday. It was introduced in 1980 when Greenland was legally a part of Denmark without local rule. The most other EU Overseas countries and territories do not observe summer time. Exceptions, based on company decisions, are the northeastern coast around Danmarkshavn (UTC year-round) for Thule Air Base (which follows Atlantic Time and observes in accordance with US and Canadian rules).