Side-chapel

The term chapel usually refers to a place of prayer and worship that is attached to a larger, often nonreligious institution or that is considered an extension of a primary religious institution. It may be part of a larger structure or complex, such as a college, hospital, palace, prison, funeral home, church, synagogue or mosque, located on board a military or commercial ship, or it may be an entirely free-standing building, sometimes with its own grounds.Chapel has also referred to independent or nonconformist places of worship in Great Britain—outside of the established church.

Until the Protestant Reformation, a chapel denoted a place of worship that was either at a secondary location that was not the main responsibility of the local parish priest, or that belonged to a person or institution. The earliest Christian places of worship are now often referred to as chapels, as they were not dedicated buildings but rather a dedicated chamber within a building. Most larger churches had one or more secondary altars, which if they occupied a distinct space, would often be called a chapel. In Russian Orthodox tradition, the chapels were built underneath city gates, where most people could visit them. The most famous example is the Iberian Chapel.

Although chapels frequently refer to Christian places of worship, they are also commonly found in Jewish synagogues and do not necessarily connote a specific denomination. In England—where the Church of England is established by law—non-denominational or inter-faith chapels in such institutions may nonetheless be consecrated by the local Anglican bishop. Non-denominational chapels are commonly encountered as part of a non-religious institution such as a hospital, airport, university or prison. Many military installations have chapels for the use of military personnel, normally under the leadership of a military chaplain.

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