About two-and-a-half hours NE of Québec City, take a ferry from the Charlevoix coast to the Île-aux-Coudres, a 7x3 mile (11x5km) island in the St.-Lawrence. Here the wide river becomes an arm of the sea; belugas ply the brackish waters.
Settled by the French in the 1700's, about a thousand people still call this farm-and-orchard-covered island home. Stone chapels line the ring-road (perfect for cycling), and near the 19th-century windmill and twin-steepled Église St.-Louis, you can see one of the small boats that used to assure communication and transport between this island and the mainland.
Until a few decades ago when regular ferry service was established, the island was pretty much cut off during the winter, except for hearty souls who would traverse the river by combining canoeing through unfrozen stretches and then getting out of their canoe to pull it over the ice floes...
Today, a car-ferry runs every hour from the village of St.-Joseph-de-la-Rive.
For more info about the island: http://www.tourismeisleauxcoudres.com/home.aspx
For ferry schedules/fares: http://www.traversiers.gouv.qc.ca/ferries/lisle-aux-coudressaint-joseph-de-la-rive_18.php