Directions to Trail Head. From Ashton, Idaho, travel east on State Highway 47, the Mesa Falls Scenic byway.  While traversing the fertile farm lands, you might catch a glimpse of the Teton mountain range to the South and East.  After a short while the highway will turn to the left heading North and then North East.  Soon you will leave the plateau of farm land and descend in the warm river canyon.  In the canyon bottom, you will cross the river several times.  Just as you cross the last bridge and the road starts to climb out of the canyon there will be a turn off to the right to the Warm River campground.  Look for the sign.  Prior to entering the campground, there are several places long the road for parking.  If you want to pay the fees for day usage of the campground, you get a little closer to the trail head.  The trail head is on the northeast corner of the large parking lot near the large covered pic nic area.

Trail.   For a short distance the trail overlays a paved walk path that soon forks to a wooden platform on the rivers edge. The trail continues up the canyon.  You will come to a gate across the trail.  Just go around it.  The trail slowly ascends the west side of the canyon, leaving the river below.  Being a former rail road bed, the trail has a consistent and gradual climb.  The trail is well maintained, allowing you to ride side by side.  Take time to enjoy the wonderful scenery and animal life.  After about three miles you will arrive at the tunnel.  The snowmobilers cover the bottom of tunnel with wood chips since there is no snow inside the tunnel.  The snowmobiles create a washboard affect that you will find interesting as you travel through the dark.  The return trip will be a quick, easy glide back to the campground.

If you still have the some energy, you can continue up the trail beyond the tunnel another five miles to visit the Warm River Springs. Beyond the tunnel, the trail continues its gentle climb.  There will be a few rocky spots and two cattle guards.  Eventually the trail levels out when you reach the plateau (really it it the floor of the Island Park Caldera.)  The trail will take you through meadows until you reach the junction of the forest service roads 367 and 154, about three miles beyond the tunnel.  It is impossible to miss the intersection because there is a stop sign that seems so out of place.   Turn right, heading East to visit the Warm River Springs.  The trail wonders through several meadows before returning to the canyon by way of a steep descent that is fun going down but good exercise going back up.  At the springs you will find a Forest service cabin that is available to rent.

For the adventuresome, you can continue up the rail road bed until you reach Big Springs and West Yellowstone.  If you are really lazy, you can drive your car to the parking lot at Bear Gulch and walk the quarter mile to tunnel as well.  Regardless how you get there or how far you go, this is a fun, pleasant trip.