Afon Hepste (Welsh pronunciation: [ˈhɛpstɛ]) is a river in Powys, Wales, though partly forming the county's border with Rhondda Cynon Taf.

It enters onto the Carboniferous Limestone outcrop near this point and sections of its course downstream remain dry in all but flood conditions as the flow disappears underground.

[1][2] The Hepste plunges over a band of resistant gritstone to form Sgwd yr Eira (translated from Welsh as 'fall of snow').

A public footpath runs behind this fall, making it one of the most popular destinations in an area that has become known as Waterfall Country.

One mile downstream of the fall, the river joins the Afon Mellte near to the village of Ystradfellte.