Thunder Pass Trail

Thunder Pass sits high on the Never Summer Mountains, straddling the boundary of Rocky Mountain National Park — but the honest, uncrowded way to reach it is from our side, up out of the Cameron Pass and State Forest State Park country at the very top of the Poudre. COTREX maps the trail as about 3.4 miles of dirt tread that begins on State Forest land, crosses a short stretch of Canyon Lakes / USFS ground, and then tips over the divide into the national park. It climbs through the upper Michigan River drainage — open, wind-scoured, and quiet — toward the saddle that gives the pass its name.

This is a through-trail with two different sets of rules, and it pays to know where you are. On the lower, State Forest and Forest Service portion, bikes and dogs are allowed alongside hikers and stock; but the moment you cross into Rocky Mountain National Park — roughly at the pass itself — bikes and dogs are both off-limits for the rest of the way down. If you are bringing a dog, this is a turn-around-at-the-boundary hike. It is high, exposed country with little shelter, so treat the weather seriously and check current conditions and access with State Forest State Park and the Canyon Lakes Ranger District before you go.

Trail Facts

Getting There

Reached from the Cameron Pass area at the very top of the Poudre Canyon on CO-14, through State Forest State Park and the upper Michigan River / Michigan Ditch country on the west side of the pass. The exact trailhead and current parking change with the season — confirm the route on the map and with State Forest State Park and the Canyon Lakes Ranger District before heading up.

0.0 mi	North access — approach from State Forest / Cameron Pass
At the divide	Thunder Pass — Rocky Mountain National Park boundary (dogs & bikes stop here)
3.4 mi	Trail continues down into RMNP toward the Michigan River headwaters

Know Before You Go

• Two sets of rules. COTREX shows hiking and horses allowed the whole way; bikes and dogs are allowed only on the lower State Forest and Forest Service portion.
• No dogs past the pass. The trail crosses into Rocky Mountain National Park at Thunder Pass — dogs are not allowed on any national-park section, so plan to turn a dog around at the boundary.
• Part of the network. This is our northern approach to Thunder Pass from the Cameron Pass / State Forest side, linking into the Never Summer high country and the national park beyond.
• Check conditions first. High, exposed terrain with fast-changing mountain weather — confirm current conditions and access with State Forest State Park and the Canyon Lakes Ranger District.