The Supertest Ladies Open was a golf tournament on the LPGA Tour from 1966 to 1969.[1] It was played in Ontario, Canada at the Sunningdale Golf Club in London from 1966 to 1967 and at the Bayview Golf & Country Club in Thornhill from 1968 to 1969. It was the first LPGA Tour event to be played in Canada. The title sponsor was Supertest Petroleum, a Canadian petroleum company.