Elizabeth II was Queen of Guyana from 1966 to 1970, when Guyana was independent sovereign state with a constitutional monarchy. She was also the Sovereign of the other Commonwealth realms, including the United Kingdom. Her constitutional roles were delegated to the governor-general of Guyana. The Queen visited Guyana on 4–5 February 1966, where she opened the Queen Elizabeth II National Park (now Guyana National Park). She toured Guyana as Head of the Commonwealth on 19–22 February 1994.