Hill Fort

I

Introduction

Hill Fort, defensive stronghold usually built on a hill-top location and consisting of one or more lines of ditches and ramparts that were built of earth, timber, and stone. The term most commonly applies to strongholds built in western Europe during the Late Bronze Age and the pre-Roman Iron Age.

II

Historical Development

The main period of the development of hill forts came in the Iron Age, and is closely associated with the political, social, and economic development of the Celtic-speaking tribes who dominated most of Europe at the time. The earliest hill forts were built shortly before 1000 bc and probably developed from the defended hill-top settlements of the Late Bronze Age. In Britain there are several varieties of these. At Staple Howe (Yorkshire) the summit of a prominent chalk knoll was occupied by an oval enclosure protected by a timber palisade: within were two large timber houses and a four-post structure, originally interpreted as a large granary, but which makes more sense as a watchtower. Other palisaded sites were later rebuilt on a larger scale as true hill forts: Eston Nab (Yorkshire), the Breiddin (Powys), and Breedon-on-the-Hill (Leicestershire) all began as simple sites of this type. By the very end of the Late Bronze Age (around 800-700 bc), more elaborate forms of construction were to be found. At Dinorben (Denbighshire) was built a rampart of stone and rubble strengthened and revetted with timber, and at Mam Tor (Derbyshire) a 6-hectare (15-acre) site was enclosed by a simple dump rampart of stone rubble.

III

Design

The earliest hill forts were simple in design, consisting of a single line of defences encircling the top of a hill. In cases where the defences included a bank or rampart of earth and rubble, there was an outer ditch, created when the rampart material was dug. Entrances simply took the form of a gap in the defences fitted with a gate. By the beginning of the Iron Age, however, greater variety of design began to appear, often following styles originally developed on the continent of Europe. The timber-framed box rampart, seen at sites such as Ivinghoe Beacon (Buckinghamshire) and Grimthorpe (Yorkshire), consisted of a solid row of posts at the front and rear of the rampart, supporting vertical faces of timber to produce a great box, which was filled with earth and rubble. In areas where suitable stone was freely available, the box rampart was sometimes revetted with dry-built stone walls, though timber lacing was also used to give strength to the rampart. When such timber-laced ramparts caught fire, the heat could be sufficient to fuse the stone and rubble into a glassy substance, which can be seen in the vitrified defences of certain hill forts in Scotland. Some ramparts were built entirely of stone, such as the final phase of the defences at Dinorben, and a few sites were protected merely by massive stone walls without any ditch, as at Tre’r Ceiri (North Wales). Many later hill forts were defended by simple dump ramparts of rubble, with a continuous slope running from the top of the bank to the foot of the ditch, a type of defence known as a glacis.

As the structure of hill forts developed from palisade, through box rampart, to glacis, so the layout of the defences themselves became also more elaborate. The most significant development was the adoption of two or more lines of defence, creating such multi-vallate (multi-walled) forts as Maiden Castle (Dorset), perhaps the most impressive of all surviving hill forts. Entrances also became increasingly complex, and often incorporated guard chambers and flanking outworks and barbicans to ensure that attackers faced a barrage of missiles from the sides as well as from the front.

IV

Purpose

It is clear that hill forts were built primarily as defensive structures, and that they were intended to function as strongholds during a time when tribal warfare seems to have been common. A more specific role played by hill forts, however, developed through time. Although the early site at Grimthorpe contained no clear evidence of settlement (perhaps a reflection of the small scale of the excavations), it contained large numbers of four-post structures, usually interpreted as granaries. Similarly, other sites have consistently been shown to have contained elaborate provision for the storage of food, particularly grain: Danebury (Hampshire) is just one of many sites that were honeycombed by storage pits and grain silos. These stores may have been a strategic reserve for times of trouble, but might also represent the private stores of a leader or ruler who was supported by a tax on the produce of the area. Certainly, hill forts also contained settlements, which by the Late Iron Age could reach a high density: sites such as Maiden Castle contained a considerable population, and may have represented the earliest beginnings of urban life in this area. Hill forts were probably the seats of local leaders or even, in the late Iron Age, of tribal kings, who would have been surrounded by their own warriors and a host of dependent traders, craftsmen, and families. Industrial activity was common, attracted by the patronage of the ruling elite: for example, Traprain Law, near Edinburgh, was an important centre for the manufacture of small and ornamental bronze objects. Religious centres are also known, at Maiden Castle and possibly elsewhere.