Mrs. Lyndon B. Johnson and Mrs. Lester B. Pearson together opened Roosevelt Campobello Park on the twentieth day of August 1964. Lyndon Baines Johnson, President of the United States of America, and Lester Bowles Pearson, Prime Minister of Canada, together laid the cornerstone of this Reception Centre on the twenty-first day of August, 1966. Her Majesty Queen Elizabeth The Queen Mother declared the building open on the thirteenth day of July, 1967.