What should I wear and bring?

Bring a warm jacket, even in high summer. The canyon stays at a constant 10 degrees, and the humidity and spray from the Lütschine make it feel colder. Wear sturdy shoes with a non-slip sole: the wooden walkways can be wet and slippery. A camera or action cam is welcome, drones are not allowed. For the rest, whatever you'd wear for an easy walk is enough.