Corbel arch

Corbel arches and vaults require significantly thickened walls and an abutment of other stone or fill to counteract the effects of gravity, which otherwise would tend to collapse each side of the archway inwards.

[1] The Newgrange passage tomb, built sometime between 3200 and 2500 BC during the Neolithic period, has an intact corbel arch (vault) supporting the roof of the main chamber.

[citation needed] During the Fourth Dynasty reign of Pharaoh Sneferu (c. 2600 BC), the Ancient Egyptian pyramids used corbel vaults in some of their chambers.

In particular, corbelled burial vaults constructed below the floor are found in Middle Bronze II-III Ebla in Syria, and in Tell el-Ajjul, Hazor, Megiddo and Ta'anach in Canaan (today's Israel and Palestine).

[citation needed] Nuraghe constructions in ancient Sardinia, dating back to the 18th century BC, use similar corbel techniques.

[4] Greece has a long list of surviving or archaeologically studied corbelled arches and vaults used for bridges and a multitude of other structures, dating from the Mycenean and Minoan, the late Classical, and the Hellenistic periods.

[5] The ruins of ancient Mycenae feature many corbel arches and vaults, the Treasury of Atreus, built around 1250 BC, being a prominent example.

"[8] The earliest large buildings of the Delhi Sultanate established in 1206 after a Muslim invasion used Indian workers used to Hindu temple architecture, but the patrons were used to Central Asian styles that used true arches heavily.

By around 1300 true domes and arches with voussoirs were being built; the ruined Tomb of Balban (d. 1287) in the Qutb complex in Delhi may be the earliest survival.