Winnipeg's POLO PARK CENTRE was built on land previously devoted to a horse racing track. Its main store was Simpsons-Sears, with the tenant list of forty including an S.S. Kresge 5 & 10 and two supermarkets...Dominion and Loblaws. The mallway was enclosed in 1963, with a second level being added in 1984-1986. 
Photo from www.polopark.ca