The Sulby River rises in the nearby Snaefell Mountain foothills and flows through the glen, and it also contains the A14 road.
At the bottom of the glen, about 1 km south of the village of Sulby, the river emerges into the island's northern plain.
By the riverside just below this point is Sulby Claddagh, a local beauty spot and camp site.
This is managed, preserved and maintained in a semi-natural state by a government agency: the Forestry Amenity and Lands Directorate of the Department of Environment, Food and Agriculture.
At the entrance to Tholt-y-Will Glen is a small car park and picnic area.