Turin’s Castello di Rivoli was constructed in the 17th century as a royal residence for members of the House of Savoy. Within the castle’s ancient walls, the Manica Lunga was built in 1630, to house the Savoy Gallery. For Olafur Eliasson, a master of spacial intervention, the ancient walls serve as the perfect backdrop for his sensory installation. Within the wing’s entirety (482 feet long and 19 wide), Eliasson has constructed a labyrinth made of color, light, and water. The show runs in conjunction with his major exhibition at Palazzo Strozzi. —Elena Clavarino