We went just to see the falls (we didn't stay overnight in the provincial park). There were two different ways to park. You could enter the park for $14 for a day or just cross over the bridge to a parking lot where you can just pay about $5.50 for 2 hours. There were two toilets in the parking lot. They were the usual that you get at provincial parks (non flushing).
Wear water shoes. The rocks are slippery. A bunch of people were jumping off a waterfall into the water (about a 2 m drop). The youngest jumper looked to be about 5 or 6 years old (very brave little girl). Several older kids and teens and adults jumping too. When we got there some of the teens seemed to know where to jump safely (not onto rocks) and they guided the rest of us.
I would not bring little kids here to play in the water. The current could knock a little kid off their feet. A one hour visit here is plenty.
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