Barrel-vaulted ceilings may be having a moment as of late—but they’ve been around for a long, long time. Arched, adobe-clay ceilings made thousands of years ago still stand in Egyptian tombs; the Romans used intersecting barrel vaults (also known as groin vaults) to support such outsize classics as the Pantheon; and in the third century, Persian architects built the Taq Kasra, a vault soaring 110 feet high and over 80 feet wide.

Medieval and Renaissance architects developed rib vaults and fan vaults to build increasingly ornamented cathedrals, while Spanish architects simplified, perfecting the shallow-arched, thin-tiled Catalan vault. In each of these historical moments, barrel vaulting was used for practical reasons as well as beauty—the form offers structural efficiency, can be made from locally-sourced materials, is often fireproof, and can be constructed at low cost. Modern architects appreciate these advantages, and many see barrel vaulting as a green-building technique. Read on for a look at 18 homes with beautifully executed barrel-vaulted ceilings.