The Muscle Monster, in Japan’s Kanagawa Prefecture, is a giant-sized jungle gym for adults, and especially ninja wannabes.
Perched on the edge of a mountain, it has all the spaces and ladders needed for 92 different potentially risky ways to swing, jump and climb from place to place—as long as you’re 45″ tall and under 264 pounds, and old enough.
The structure is over 50 feet tall, and is perched on the edge of a mountain; its 3 levels also include an observation deck and safety ropes. Plenty of them. The attraction will open on March 10, about an hour from Tokyo.