When in Quebec City, odds are you will walk along this section called the Terrasse Dufferin which is like a boardwalk. We went during the winter time and if you go then, I have no doubt that you should visit this area for the slide that they have. I'm not sure if it exists during other months, but in the winter, you pay a few dollars for a sled that you take up a really big slide and you sled down at really fast speeds.
Even if you don't come during winter, I imagine that the views and the atmosphere of the area is worth paying this area a visit. And you can't really go wrong since it is free!
Come back next Friday for another Past Point of Interest!