The B3417 was designated around 1990, mainly to aid HGV drivers accessing the China Clay works at Lee Moor.
The road starts on the B3416 in Plympton and heads north, immediately going under the railway line and then meeting a roundabout where it turns right. After passing an industrial estate the road uses to TOTSO left onto a winding S1 road but this section has been bypassed and so the B3417 continues east a bit further before turning left. Old and new roads rejoin and the B3417 remains S2.
We continue north along the eastern side of the valley of the Tory Brook. Presently the road goes over a cattle grid and becomes an unfenced road over Crownhill Down, on the edge of Dartmoor. After a few bends and another cattle grid the road passes through a wood with a wall on either side; we could easily be closer to the centre of Dartmoor were it not for the industrial buildings looming ahead. We go round one of the china-clay works (with signs advising HGV drivers to use our road to get to the A38) and then continue round a few more corners to reach a T-junction. The B3417 ends here on an unclassified road, although there are other works nearby.