Reached by paved Three Mile Canyon Trail,
with return via Rail Trail
The Princess Di trail is a singletrack trail that hugs the hillside east of Promontory. The track is narrow, with some areas of loose volcanic rock that create tricky traction on the many tight switchback turns. This makes the trail "expert" in technical requirement, although intermediates can ride it by dismounting on most of the turns.
Trailhead parking is at 6500 feet elevation. Top altitude is 7300 at the ridgeline 10 miles into the ride, bottom 6300 at the Rail Trail. You'll gain, lose, and regain altitude for about 1800 total feet of climbing.
The last long climb on the singletrack gains 400 feet over about 1.5 miles, putting you on top of the ridge at 7300 feet. To the west are views over Park City and Jeremy Ranch. To the east, Rockport Reservoir sits in front of the Uintah Mountain foothills.
Near the bottom, there's a long straight downhill as you and the Promontory Road follow a small creek down toward I-80.
Turn right and cross I-80. Notice the little tree-lined pit to your right. Hike down into the creek (dry in August), turn right, and go through the tunnel under the southbound lane. In between freeway lanes, you'll find the Rail Trail. Turn right and ride uphill 4 miles back to the trailhead.
0.0 Back to road N40 43.475 W111 28.309
Cross road, L on paved trail
Begin Three Mile Canyon paved trail
0.3 Keep straight on paved trail at all crossings
N40 43.449 W111 28.082
(R = to South Canyon Trail)
2.4 Top of ridge, begin to descend
3.0 L on singletrack (end of pavement 2010)
N40 44.537 W111 26.103
Begin Princess Di singletrack
7.2 Top of ridge, angle L across road to ST
N40 46.140 W111 26.772
9.4 Drop R on ST as you hit clearing with bldg
N40 46.684 W111 27.391
10.5 Plunge down to road, turn R and go over I-80
N40 46.512 W111 28.066
Immediately after freeway, drop R into "hole"
N40 46.530 W111 28.161
R into drain tunnel, go under southbound land
R on Rail Trail in between lanes of freeway
14.5 L into parking area
Bathroom: Outhouse at trailhead.
Water: None at trailhead. Convenience store 1/2 mile away.
Camping: None in immediate area. Nearby at Rockport, Echo, or
Jordanelle Reservoirs.
Bike Services: Multiple shops with rentals and repairs in Park
City.
Single-page riding guide: View to print
GPS track files (right-click and "Save as..."):
GPX course for loop
GPX area trails
Large-format area topo map (900K): View
Lodging, camping, shops: Links to area resources