Notre Dame de Paris

Cathedral of St. Denis

Amiens Cathedral

Cathedral of St. John the Divine

An upper level gallery space in an ancient basilica

A double-shelled dome held up by a shallow drum

Curved, multi-leveled bench seating often placed in the apse of a church

A type of royal tomb popular in the 5th and 6th centuries CE

Flying buttresses

Barrel vaults

Corinthian columns

Round arches

Hagia Eirene and the Church of SS. Peter and Paul

The Church of SS. Peter and Paul and the Hagia Isidorus

Hagia Polyeuktos and the Church of SS. Sergius and Bacchus

The Church of SS. Sergius and Bacchus and the Church of SS. Peter and Paul

The Qibla

The Dome of the Rock

The Mi'raj

The Kaaba

Decorative inscription on a mosque

A horseshoe-shaped arch

A tower outside a mosque where Muslims are called to prayer

Alternating bands of differently colored masonry

Daereungwon Tumuli, Korea

Cahokia, USA

Twin Pyramids, Tikal

Pyramids of the Sun and Moon, Teotihuacan