Hi captains and stokers,
Although it might be getting a little late this season, you should consider this absolutely marvelous tour. It starts in Toronto's beautiful Union station. You and your bike get on a VIA train to Niagara Falls. At the falls you are greeted by members of the cycling committee who will assist you with your tour.

Ours was Saturday to Monday and we really enjoyed the tour. Check out the story on my crazyguyonabike journal

More info on the bike train here