Take the Canadian side boat tour for rainbow shots.

The Hornblower tour (Canada) gives you a better angle. You approach the Horseshoe Falls head-on, and the sun is usually behind you in the afternoon. That puts the mist right in front of you with the light hitting it from behind — prime rainbow conditions.

The Maid of the Mist (US side) runs closer to the American and Bridal Veil Falls, but the boat sits more parallel to the main curtain. You get spray but not the same direct sun-mist alignment. Rainbows happen, but they’re smaller and harder to frame with the full falls.

If you want that classic shot — big rainbow arcing across the base of the Horseshoe Falls — go in the late afternoon from the Canadian boat. Early morning works too, but the sun lifts the rainbow higher. Either way, bring a rain cover for your lens.