It takes its source at the Trient Glacier in the Mont Blanc Massif and joins the Rhone between Vernayaz and Martigny.

The Trient is essentially a wild alpine river mostly fed by glacial runoff.

High in the Alps it is fed by numerous small streams that run down the surrounding mountains.

Notable streams are the Eau Noire (collecting the Barberine below the Lac d'Emosson) and the Triège.

Shortly after passing the Trient Gorges, the river flows into the Rhone just south-east of the village of Vernayaz.