Mont-Royal Montreal.

You should definitely take the time and effort to climb up to Mont-Royal - the big hill located in the middle of the city. From the top, you'll get a really nice view to downtown and almost the entire city. There are buses too to take you to the top but I think it's more fun and more rewarding if you climb all the way up by yourself! You can also do activities such as bicycling or skiing in the area. Every Sunday during the summer people gather on the grass to chill out and dance as some 'tam-tam' players are providing the music.