Oriole and the Mariposa (evocative of Stephen Leacock's zany stories) wait to show tourists some pleasing views of the Toronto Islands and Lake Ontario. The Great Lakes cover an enormous surface (about a fifth of the total surface of the huge province of Ontario), and contain one fifth of the earth's surface freshwater. They're traversed by enormous numbers of cargo ships. "Lakers" stay within the lakes, while "salties" are oceangoing ships that travel through the St. Lawrence Seaway into the Atlantic.
I got lucky on my Oriole trip: there were only a handful of passengers aboard and the commentary was clear and informative. I learned how much the Toronto waterfront has been filled in; ships once docked near the Royal York Hotel. A kilometer inland from the current dock, this old Toronto landmark is now dwarfed on all sides by enormous glass towers.