The island has a fine series of surviving megalithic monuments with passage graves such as La Varde and outstanding examples of ornate statue-menhirs as at Câtel (Kinnes, 1981). There are distinctive local variants, as in the cellular elaboration of the Déhus tomb and the regional style of cist-in-circle monument. In terms of islands as laboratories of prehistory it is instructive to note that these structures survive only where protected from the ravages of agriculture, here on the sterile sand-drift of the north and the rocky promontories of the west coast. Sporadic records and the place-name evidence studied in detail by de Guérin (1921) indicate the extent and unevenness of destruction. Of some 70 monuments thus recorded only 12 survive in any recognizable state, and earlier density at about 1 per sq. km is an important corrective to attempts at territorial analysis based on extant distribution.