The route begins at PTH 2 south of Wawanesa, and terminates at the Trans-Canada Highway just north of Douglas.

[1] PR 340 was originally a much longer provincial road in comparison to its current distance.

From Belmont, PR 340 continued north, with small jaunts eastward, before meeting PTH 2 west of Glenboro.

The highway rejoined its current configuration just north of the community after a short crossing over the Assiniboine River at Treesbank Ferry.

The sections of the original route that were not redesignated are now maintained by the rural municipalities of Oakland, South Cypress, and Strathcona.