Coal of a permanent brazier of coal on the altar of Minerva at Aquae Sulis (modern day Bath), although in fact easily accessible surface coal from what became the Somerset coalfield was in common use in quite lowly dwellings locally. Evidence of coal's use for iron-working in the city during the Roman period has been found. In Eschweiler, Rhineland, deposits of bituminous coal were used by the Romans for the smelting of iron ore. No evidence exists of the product being of great importance in Britain before about AD 1000, the High Middle Ages. Mineral coal came to be referred to
Christianity in Roman Britain introduced Roman counterparts were venerated in the region, sometimes syncretising together, as in cases like Apollo-Cunomaglus and Sulis-Minerva. Romano-British temples were sometimes erected at locations that had earlier been cultic sites in the pre-Roman Iron Age. A new style of "Romano-Celtic temple" developed which was influenced by both Iron Age and imperial Roman architectural styles but also unique from both; buildings in this style remained in use until the fourth century. The cults of various eastern deities had also been introduced to Roman Britain, among them those of the deities Isis, Mithras, and Cybele; Christianity was just one of these