High Quality Content by WIKIPEDIA articles! The Erme is a river in south Devon, England. From its source on Dartmoor it flows in a generally southerly direction past some of the best-preserved archaeological remains on the moor. It leaves the moor at the town of Ivybridge and continues southward, passing the settlements of Ermington, Modbury and Holbeton. Near Holbeton it becomes a ria and empties into the English Channel in Bigbury Bay, between the rivers Yealm and Avon.