It connects the hamlets of Miami, Stephenfield, and indirectly, Haywood.

It heads due north as a two-lane gravel road along the western side of town before leaving Miami and travelling through rural farmland for several kilometres.

Entering the Rural Municipality of Dufferin, the highway crosses both PR 245 and the Boyne River as it passes through the hamlet of Stephenfield before narrowing to one lane as it continues north through rural areas.

PR 338 traverses a switchback before coming to an end at an intersection with PR 305, as Road 35W continues on for six kilometres (3.7 mi) to both PTH 2 (Red Coat Trail) and Haywood.

[1][2] PR 338 is currently a shadow of its former self, previously stretching for 96.2 kilometres (59.8 mi) from Thornhill to just west of Newton, including both the current route plus a long concurrency (overlap) with PTH 2 (Red Coat Trail) through Haywood.