What exactly is bouldering? Bouldering is climbing on walls up to 4m high, without rope, harness or other aids. The bouldering gym is the hippest alternative to the gym; bouldering makes you fit, strong, slim and flexible! In total you will find 198 circuit boulders spread over 7 levels. So whether you are advanced or just getting started: climbing in Monk Eindhoven is for everyone.