and the source of the Erme are two of the thirty-three places that delineate the ancient boundary of the Forest of Dartmoor. On this stretch, a short stream flowing down Hortonsford Bottom from Langcombe Hill also joins the river from the south. Between Stingers Hill and Redlake the river turns southward into an area known as The Meadow, where it is crossed by the Upper Erme stone row, the longest on Dartmoor at . For the next mile or more downstream from here there are extensive archaeological remains on the river's banks, most notably Erme Pound (the highest and largest Bronze Age enclosure in the area), Downing's House (a well-preserved "tinner's cache" or "beehive hut" with much of its roof preserved), and a number of tinner's huts and blowing houses. As the river reaches the edge of the high moor, it flows through the gorge it has cut between Stalldown Barrow on the west and Piles Hill to the east. Here, on the eastern bank, lies Piles Copse which is one of the few areas of ancient woodland on Dartmoor and a Site of Special Scientific Interest. Although the moorland valley of the Erme today appears to be natural and unspoiled, the entire valley floor from its source down to Piles Copse is artificial, being created by the extensive tin-streaming operations that took place between the 4th and 14th centuries. Supporting evidence for this was provided by a study published in 2004 which showed that phases of aggradation occurred lower down the valley between the 4th century and the 7th century, and in the 13th century. Leaving the open moor, the river passes into enclosed land and under its first road bridge at the hamlet of Harford. At this point it is joined by the minor stream of Butter Brook, with its now disused reservoir. From Harford down to the boundary of the national park, which here follows the main railway line between Plymouth and Exeter, much of the river's course is in woodland and is a popular site for kayaking and canoeing, especially in Long Timber Woods. Ivybridge to Holbeton After leaving the national park, the river continues southward, passing through the centre of the town of Ivybridge where it formed the source of the town's prosperity by powering a grist mill, a paper mill and a fulling and tucking mill. In 1813 the only bridge over the river