At 1,353 feet, the Al Hamra Firdous Tower in Kuwait is the tallest building in the world with one side made of stone. Before the advent of steel frames, which made glass curtain walls possible, masonry helped buildings stand tall. Instead of choosing stone for its strength, though, engineers and architects at SOM chose it to help keep the building cool. The tower’s monolithic facade faces south, where stone helps mitigate heat loading from the broiling sun. The rest of the building is covered entirely in glass, maximizing views across Kuwait City.