No equipment needed but you could use Nordic poles (retractable, lightweight). I don’t like to carry them, but reluctantly admit that they're knee savers on the way down.
Klettersteig (aka Via Ferrata) is kind of an intermediate step between hiking and free climbing. You’ll need special equipment to access this type of mountain playground, made of narrow trails, steep precipices, and steel cables and ladders built into the rock walls.
A trip to Germany must include a trip to a Klamm (gorge), a limestone slot canyon cut by the rush of cold clear turquoise waters. These steep narrow Klamms follow winding rock walls through spectacular waterfalls, rock staircases, and wooden footbridges. Bring a rain jacket because you will get dripped on and the air is cool and fresh (as the Germans say).
Klamms are great for kids because of the nonstop roar and spectacle of the white water and the many paths, tunnels, and bridges.