Chancel arch

In church architecture, the chancel is the space around the altar, including the choir and the sanctuary (sometimes called the presbytery), at the liturgical east end of a traditional Christian church building. It may terminate in an apse. It is generally the area used by the clergy and choir during worship, while the congregation is in the nave. Direct access may be provided by a priest's door, usually on the south side of the church. This is one definition, sometimes called the "strict" one; in practice in churches where the eastern end contains other elements such as an ambulatory and side chapels, these are also often counted as part of the chancel, especially when discussing architecture. In smaller churches, where the altar is backed by the outside east wall and there is no distinct choir, the chancel and sanctuary may be the same area. In churches with a retroquire area behind the altar, this may only be included in the broader definition of chancel.

In a cathedral or other large church there may be a distinct choir area at the start of the chancel (looking from the nave), before reaching the sanctuary, and an ambulatory may run beside and behind it. All these may be included in the chancel, at least in architectural terms (see above). In many churches, the altar has now been moved to the front of the chancel, in what was built as the choir area, or to the centre of the transept, somewhat confusing the distinction between chancel, choir and sanctuary. In churches with less traditional plans the term may not be useful in either architectural or ecclesiastical terms. The chancel may be a step or two higher than the level of the nave, and the sanctuary is often raised still further. The chancel is very often separated from the nave by altar rails, or a rood screen, a sanctuary bar, or an open space, and its width and roof height is often different from that of the nave; usually the chancel will be narrower and lower.

In churches with a traditional Latin cross plan, and a transept and central crossing, the chancel usually begins at the eastern side of the central crossing, often under an extra-large chancel arch supporting the crossing and the roof. This is an arch which separates the chancel from the nave and transept of a church. If the chancel, strictly defined as choir and sanctuary, does not fill the full width of a medieval church, there will usually be some form of low wall or screen at its sides, demarcating it from the ambulatory or parallel side chapels.

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