River Esk, Dumfries and Galloway

The River Esk (Scottish Gaelic: Easg), also called the Border Esk, is a river in Dumfries and Galloway, Scotland, that flows into the Solway Firth. It also flows for a small way through the English county of Cumbria before entering the Solway.

The river rises in the hills to the east of Moffat and its two main tributaries, the Black Esk and the White Esk, merge at the southern end of Castle O'er Forest. It flows south east through Eskdale past Langholm before merging with Liddel Water (which defines the border between Scotland and England. Before passing Longtown the river enters England and merges with the River Lyne and enters the Solway Firth near the mouth of the River Eden.

It was formerly one of the boundaries of the Debatable Lands as marked by the Scots' Dike.

The Scotland Act 1998 (Border Rivers) Order 1999 provides that functions relating to the management of salmon, trout, eels and freshwater fish in respect of the whole of the River Esk remain with UK ministers: the Border Esk and its tributaries are the only rivers in Scotland where an Environment Agency rod licence is required for angling.

The various tributaries of the Esk are described proceeding downstream.

The White Esk arises as the Glendearg and Tomleuchar burns merge then flow south through Eskdalemuir Forest capturing the waters of the Garwald Water at Garwaldwaterfoot then continuing by the village of Eskdalemuir into Castle O'er Forest. It is followed by the B709 road for much of its course. The headwaters of the Black Esk feed into the Black Esk Reservoir, from the foot of whose dam, the Black Esk flows south to Sandyford where it is crossed by the B723 road. It then turns sharply east then southeast passing Castle O'er on its way to meet with the White Esk to form the River Esk.

...
Wikipedia