Olympic Stadium is a multi-purpose stadium in Montreal, Canada, located at Olympic Park in the Hochelaga-Maisonneuve district of the city. Built in the mid-1970s as the main venue for the 1976 Summer Olympics, it is nicknamed "The Big O", a reference to both its name and to the doughnut-shape of the permanent component of the stadium's roof. It is also disparagingly referred to as "The Big Owe" in reference to the high cost of its construction and of hosting the 1976 Olympics as a whole.
The stadium is one of the largest by seating capacity in Canada. After the Olympics, artificial turf was installed and it became the home of Montreal's professional baseball and football teams. The Montreal Alouettes of the CFL returned to their previous home of Molson Stadium in 1998 for regular season games, but continued to use Olympic Stadium for playoff and Grey Cup games until 2012. Following the 2004 baseball season, the Expos relocated to Washington, D.C., to become the Washington Nationals. The stadium currently serves as a multi-purpose facility for special events with a permanent seating capacity of 56,040. The capacity is expandable with temporary seating. CF Montréal of Major League Soccer has used the venue when demand for tickets justifies the large capacity or when the weather restricts outdoor play at nearby Saputo Stadium in the spring months.
The stadium has not had a main tenant since the Expos left in 2004. Despite decades of use, the stadium's history of numerous structural and financial problems has largely branded it as a white elephant.
Incorporated into the north base of the stadium, inclined at 45°, and not completed until a full decade after the stadium's opening, is the Montreal Tower. At 165 metres, it is the world's tallest inclined tower. The stadium and Olympic Park grounds border Maisonneuve Park, which includes the Montreal Botanical Garden, adjacent to the west across Sherbrooke Street.