French painter Ibrahim Bouancoual was able to get out of a 12-ton rock placed in the Tokyo Palace museum.
The painter was placed inside the rock for a week and got air, water and soup through a number of small holes.
Bowenshall designed this rock himself in a way that would allow him to sit inside while keeping a limited space to put his food.
After leaving the rock, the artist said he felt that he was "in a fluid medium in a form of gravity."
"Staying inside a metal barrier creates an exciting feeling," he said.
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