A way of building in stone that can be used to bridge columns or walls or to roof chambers, but which lacks the keystones of the true arch or vault. It is built up of successive stones each of which juts out over the one below until the gap can be closed by a simple capstone. This method of roofing, sometimes labelled a false vault, was used in some of the passage graves of prehistoric Western Europe, such as New Grange and Maes Howe, and in the tholos tombs of the Mycenaean world. The corbelled arch was also a hallmark of Classic Maya architecture in Central America. Its earliest expression is in Late Chicanel tombs at Tikal and Altar de Sacrificios.