The evidence available for studying the religious beliefs and burial rituals of the Iron Age communities varies considerably both in volume and quality, and in its geographical spread over the country. There are three basic categories which can be called upon: direct archaeological data in the form of structures, cemeteries and ritual deposits; literary references concerned largely with the Druids; and less tangible assumptions which can be drawn from the limited place-name evidence and from the situation in the early years of the Roman occupation. Together this material offers the impression of a highly complex religious pattern pervading the everyday life of the people and ever present in the landscape.