Peace_Tower_PWGSC Published September 11, 2018 at 402 × 600 in 12 things you didn’t know about the Peace Tower in Ottawa ← Previous Next → The flag atop the Peace Tower measures 2.3 by 4.6 metres (7.5 by 15 feet) and is changed every working weekday and when flown at half mast. (Photo: Government of Canada, Explore the Peace Tower.)