This trail starts off the end of Thiel Road or the northern part of Glen Meadow Loop
. It heads through the Goldenrod fields by a carsonite-labeled Thunderbolt Road. It ascends the road, passing a few of the old ski buildings. When the trail seems to dead-end at Hoxie Brook
, it turns left either following the Roost Trail
or heading towards it. There is also an unnamed trail (on the right) over the brook.
At Roost Trail
, the Thunderbolt Trail tread changes from a road to a trail, and turns right. It ascends up to the Bucket Trail
. Here, the unnamed trail comes in from the right. The trail ascends, steeply, to the intersection with the Bellows Pipe Trail
, then takes a short right. It takes a left back up the hill, then reaches David's Pass
(on the left).
The trail ends at the junction with the AT. Take the AT (left) to reach Greylock's summit, or (right) to North Adams.