Young at heart won’t quite cut it in this case – you have to be physically fit to scale the steep options available for getting to the top floor of this gymnastic house.

In an overhung semi-exterior niche, the climbable wall starts as a sheltered bouldering zone but wraps up to let you reach as high as the rooftop deck area if adventurous enough.

The inside equivalent is a ladder that leads to the highest level of the home, rejoining the outside climbing wall via a window where they intersect at the upper landing.

Designed in Tokyo by Naf Architect & Design, it is hard to imagine any aspect of this passing building inspection in the United States, but at least there is a parapet at the roof level to keep the over-exuberant climber from reaching up, over and tumbling back down the even great drop on the flip side of their climb.