A nice boat ride with a guide.
A fun afternoon activity and a good way to passively learn more about Montreal.
The pictures of the biodome on the brochure were not reproducible - maybe they took the pictures from the side of the island we did not visit.
If you go, make sure to be one of the first people on the boat so you can get one of the maybe 4 couch seats. (We were not so lucky). There should be more comfy seat options!