Public building used for sheltering caravans and other travelers in the Middle East. The structure is quadrangular in form and enclosed by a massive wall that has small windows near the top and a few narrow air holes near the bottom. The central court, surrounded by an arcade and storerooms, is usually large enough to contain 300–400 camels. It is open to the sky and has a well with a fountain basin in its center. There are rooms upstairs for lodging.