This class of monument comprises two or more enclosed areas defined by a series of earthworks spaced at intervals which exceed 15m. Variation in the arrangement of the ramparts has been used as the basis for distinguishing four broad types which include: concentric enclosures; dependant enclosures; cross-bank enclosures; and, enclosures with annexes (for a detailed description of each group see section 3). In plan multiple enclosure forts are generally circular, sub-circular or sub-rectangular; the earthworks within a single site can include linear and curvilinear elements.
Multiple enclosure forts occur mainly in south-western England and are usually located on sloping ground. The division of space into a series of enclosures is generally interpreted as representing a method of containing livestock. The occurence of springs within and adjacent to a number of multiple enclosure forts has been used to support this argument.
Excluded from this description are: hillforts with an inner enclosure comprising close-spaced multivallate defences, associated with a wide-spaced concentric earthwork (eg. Castle Hill, Almondbury, Yorkshire), a dependent enclosure (eg. Croft Ambrey, Hereford and Worcester), or an annexe (eg. Bury Hill, Hampshire); and hillforts with an inner enclosure surrounded by a univallate earthwork separated by a gap in excess of 15m from a concentric multivallate enclosure with close-spaced ramparts (eg. The Wrekin, Salop).