What is an exedra?
An exedra is a semicircular or polygonal niche, often topped with a half dome, used as a sitting or conversation space. The form comes from ancient Greek and Roman architecture and was later adopted in classical and neoclassical building.
Origin
The word exedra comes from Greek (ἐξέδρα), literally meaning “outward sitting”. In the ancient world it was a resting place in:
- Gymnasia — Greek athletics schools for conversation
- Temples — separate area for priests
- Forums — public discussion and debate spaces
- Stoas — covered colonnades
Greek and later Roman philosophers gathered in an exedra to discuss — under a half dome with excellent acoustics.
Application
An exedra is characterised by:
| Feature | Description |
|---|---|
| Plan | Semicircular, polygonal or rectangular |
| Roof | Half dome (semi-dome) or flat |
| Seating | Along the wall, often in stone |
| Opening | A flat side facing the outdoor space |
In architecture
The exedra form appears in many buildings:
- Early Christian churches — as an apse behind the altar
- Roman palaces — as a reception space
- Renaissance and baroque palaces — as a garden alcove
- Neoclassical buildings — as a monumental entry
- Garden architecture — as a curved bench with overhead cover
Difference from other niches
- Apse — usually religious, behind a church altar
- Niche — smaller recess for a statue or decoration
- Conch — shell-shaped semi-dome inside a niche
- Loggia — open colonnade, not semicircular
Examples
Well-known exedras:
- Forum of Trajan (Rome) — two monumental semicircular wings
- Hadrian’s Villa (Tivoli) — several exedras in the gardens
- Trajan’s Markets — typical Roman exedra structure
- St Peter’s Square (Rome) — Bernini’s design with colonnaded exedra
Related terms
- Apse
- Niche
- Loggia
- Dome
- Stoa
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