This tour does not start from Toronto! There are a variety of different tours from this Gray Line. The details of what tour you want, will make a difference in how long the tour lasts. Any time given, is also an approximation. Especially, if crossing the border is included in the tour!
I took the tour from Toronto, it took about an hour to Niagara falls and we made 5 stops including meal, it took al day long
Starting from Toronto... 1h 30 min...till there, but the full tour is 9h
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