This is the kind of place you hear before you see.
Niagara Falls is not a single viewpoint to tick off a list. It is a full travel day - maybe a weekend - of brink-side overlooks, boat spray, rainbow mist, evening lights, and little detours downriver.
The Canadian side gives the broad postcard panorama. The US side gets you close enough to feel the river's edge. The best trip does both, with time set aside for a boat tour, a sunset walk, and a late-night look at the illuminated falls.