An ecclesiastical building used by secular communities in Britain from about ad 1000 onwards and forming the religious focus of the smallest administrative unit defined at the time, the parish. Parish churches were essentially rectangular structures aligned broadly east–west. They were designed for congregational worship and thus have two main parts: the nave at the west end which provided accommodation for the laity, and the chancel which was the domain of the priest and contained the principal altar at the far east end. Aisles provided space for additional altars and chapels. The font used for baptism was traditionally adjacent to the main entrance on the south side of the nave. During medieval times the size of the parish church and the nature and extent of its decoration were largely dependent on the wealth of the local community. The church itself is usually surrounded by its graveyard, in which might be found a lychgate, cross, anchorage, bell tower, school, and a priest's house.