A church building, often simply called a church, is a building used for religious activities, particularly worship services. The term in its architectural sense is most often used by Christians to refer to their religious buildings; they can be used by other religions.^[1] In traditional Christian architecture, the church is often arranged in the shape of a Christian cross. When viewed from plan view the longest part of a cross is represented by the aisle and the junction of the cross is located at the altar area.

La Madeleine, a Neoclassical, Catholic church in Paris, France.

The Church of Saint Simeon Stylites in Aleppo, Syria is considered to be one of the oldest surviving church buildings in the world.

Towers or domes are often added with the intention of directing the eye of the viewer towards the heavens and inspiring church visitors. Modern church buildings have a variety of architectural styles and layouts; many buildings that were designed for other purposes have now been converted for church use; and, similarly, many original church buildings have been put to other uses.

The earliest identified Christian church was a house church founded between 233 and 256. During the 11th through 14th centuries, a wave of building of cathedrals and smaller parish churches occurred across Western Europe. A cathedral is a church, usually Roman Catholic, Anglican, Oriental Orthodox or Eastern Orthodox, housing the seat of a bishop.