What is an apse?
An apse is a semicircular or polygonal projection at the end of a church nave, covered by a half-dome (concha). The apse traditionally forms the liturgical focal point of the church — this is where the altar stood and the service took place.
Origin
The apse originates from Roman architecture. In the Roman basilica (a public building for justice and commerce), the apse was located at the far end, where the judge sat. When early Christians adopted the basilica form for their church buildings, the apse became the location of the altar and the bishop’s chair.
Application
The apse appears in several forms:
- Semicircular apse — the most common form, especially in Romanesque and early Christian architecture. Visible from the outside as a rounded projection
- Polygonal apse — in Gothic architecture, the apse was often closed with three or five sides rather than a semicircle
- Flat east end — some church types (such as Cistercian churches) have a flat rear wall instead of an apse
- Triple apse system — three apses side by side, one at the choir and two at the transept
Construction
The apse is covered by a half-dome, known as the concha or calotte. In Romanesque churches, this is often painted with frescoes (Christ as Pantocrator). The apse walls are frequently furnished with niches, blind arches or windows that provide light to the choir.
In secular architecture, the term apse is sometimes used for a semicircular projection on a house or palace.
Related terms
- Absidiole
- Choir
- Vault
- Basilica
- Transept
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