The original settlement, Old Dilton, is some southeast of the present village centre at , on the banks of the Biss Brook. It now consists of a couple of farm houses and the ancient St Mary's Church. As fewer workers were needed in the local woollen industry after the introduction of greater mechanisation, many moved to the common land of the drained marsh (called Dilton's marsh) on the northern side of the ridge. By the early 19th century, Dilton Marsh had outgrown the older settlement.