A later prehistoric port is a coastal site whose inhabitants were closely involved in waterborne trading, dating to the later Iron Age, often covering an area in excess of 10 ha. The boundaries of these sites are demarcated by large earthworks (principally banks and ditches). Only a small number have been recognised, all of which are located along the southern coast of England. Sites in this class share a number of characteristics with both "enclosed" and "unenclosed" Oppida, in that all show evidence for the nucleation of settlement in the later Iron Age, together with a variety of imported materials.
Later prehistoric ports are recognised archaeologically on the basis of their coastal location, the large earthworks which define their perimeter, and the high frequency of imports that they contain. Specifically excluded from this description are enclosed and unenclosed oppida. Although these classes share a number of features in common, ports should be held as distinct on the basis of (a) their coastal position, and (b), the far wider variety of imported materials that they contain. The similarities between these different classes are such that Cunliffe (1978a; 1978b) has applied the term Oppida to characterise Hengistbury Head. Yet this denies the restricted locations in which ports occur, as well as the far wider range of imported materials which they contain, both from the continent and from other regions of England.
The range of evidence found at ports suggests that they formed the focus for a variety of productive and distributive activities, suggesting that they provided the principal channels through which cross-channel contact and trade were articulated.