Canada - Cities Service Limited, an oil exploration company based out of Calgary, Alberta, operated a test well in the Hillsborough Bay, eight miles south of Charlottetown, Prince Edward Island in the 1940's. In 1924, a survey conducted by Hugh MacKay of Sapula, Oklahoma, indicated a geological structure in Hillsborough Bay that could be favorable for the accumulation of oil. In 1942, Cities Service Limited joined with Socony Vacuum Oil Company and, in the following year, they began drilling for oil in the Hillsborough Bay. The operations were conducted by the Island Development Company, a subsidiary of Socony Vacuum Oil Company, and the drilling contractors were the Loffland Bros. Company of Tulsa, Oklahoma.