A cloister is a covered walk, open gallery, or open arcade running along the walls of buildings and forming a quadrangle or garth. The attachment of a cloister to a cathedral or church, commonly against a warm southern flank, usually indicates that it is part of a monastic foundation, "forming a continuous and solid architectural barrier... that effectively separates the world of the monks from that of the serfs and workmen, whose lives and works went forward outside and around the cloister."
