Mud Springs Trail System (Moab)

Bruce rolls a wide turn while descending Yellowcake Walk.

Mud Springs Trail System

The Mud Springs system is a set of highly-engineered flow trails machine-excavated into clay soil. Mud Springs is located around 11 miles south of Moab in San Juan County. Except for the Geiger Grind connector trail, the system is all one-way. U235 is the single climbing route, with descending on RADium and Yellowcake Walk.

The Mud Springs trails are located in a Wildlife Management Area (WMA). They are CLOSED during winter and early spring. Trails close on December 1 and re-open April 15.

Photos, video, and review by Bruce on May 23, 2026.

This system consists of broad flow trails in clay and dirt. The riding surface is wide enough to easily handle a bike trailer full of kiddies as well as three- or four-wheel adaptive cycles. The grade rarely exceeds 6% -- with the exception being a couple of not-too-steep climbing turns. The trails are quite suitable for beginning riders, assuming they have enough leg and lung to pedal 500 vertical feet uphill.

View east from U235 as we climb uphill. The peaks of the La Sals are at upper right.

Mellow climbing on U235.

The downhill trails have highly-banked turns designed for speed and flow. Even the uphill tail U235 has significant banks on the climbing turns. There will be NO ledges or rock outcrops to bang over. So unless you want to, you won't ever have to get off your seat. Smooth as butter in 2026.

Like almost all Moab-area trails, the system is well-marked with signs. Riding lines are always obvious.

But don't get the idea that these trails are boring. The twisty turns on the downhill flow beautifully. Experts will love these trails too. So if you need a break from the teeth-rattling bone-jarring roughness of the typical Moab trail, give Mud Springs a try.

The most popular loop is the combination of U235 and Yellowcake Walk, which is 5 miles and 500 vertical feet of climbing. Most riders will do a second lap to descend RADium.

View from the eastern side of the mountain as we pick a descending path.

Trailhead

Toilet at trailhead, looking north from parking.

As you drive south from Moab on Highway 191, continue until you're in open desert. At mile 11.8 from Moab's Center Street, watch for a parking area on your right. This is the first ATV staging for the Behind the Rocks trail. Don't stop here, but continue around 0.1 mile further, watching for a gravel road on your left at mile 11.9. Turn left now. This is CR 129, Yellow Circle Road.

If you find yourself driving up the hill on Highway 191, you missed the trailhead road. Find a safe spot to turn around, then find your gravel road immediately after you get down off the hill.

The gravel road will veer right to merge with another road. You should be able to spot the trailhead parking and bathroom to your right.

It's 0.4 miles from Highway 191 to the trailhead. The trailhead is one-way traffic, entering at the first opening. After you finish your ride, continue uphill to exit at the upper opening. The trailhead has a bathroom and space for around 30 vehicles.

Looking south in the parking strip. Exit at far end.

Outbound trail, from the parking area.

Primitive camping is available just uphill from the trailhead on Yellow Circle Road.

The entry to the trail system is near the downhill end of the parking strip, just south of the bathroom and vehicle entry. Head toward the hill to the east (a right turn from where you parked your car) and cross the Yellow Circle road. Pedal to the base of the hill, where the trail will split.

When you reach a trail fork -- just before a line of fence posts -- turn to the right on the one-way U235 climbing trail.

U235 Climbing Trail

On the way uphill. Notice that even the uphill turns are banked for speed.

The U235 climbing trail begins where the connector trail hits an old fence-line, 200 feet from the parking strip. Turn to the right. (The two trails to the left are the one-way downhill-only trails!)

U235 is 2.2 miles long. You'll climb from 5350 feet elevation to 5750 over 1.7 miles before descending 0.4 miles to the trail fork with RADium and Yellowcake Walk.

The U235 trail is a highly engineered flow trail, machine-built in dirt and clay. Turns have a gentle bank. The tread is wide enough for bike trailers and adaptive cycles.

The terrain around you is mostly juniper forest with bare ground between trees. Occasional bitterbrush and sage are scattered through some of the open areas.

A rare stretch of straight trail as we head east up U235. The top of the La Sal Mountains can be seen at left.

Up and around. No brutal slopes of tricky tight turns here.

The trail has several areas of gentle descending. So your overall climbing will total around 450 vertical feet before you reach the top ridgeline (with around 70 feet of overall descending up to this point).

From the ridgeline, you'll descend 100 vertical feet over 0.4 miles before you reach the fork with RADium and Yellowcake Walk.

Like the other Mud Springs trails, U235 is suitable for beginning riders, both for technical skill and for exertion level.

This is trail you ride for the joy of cruising. There are no jumps or tech challenges.

Looking back at a climbing turn on U235. (The higher trail at upper left is also U235, but we've descended slightly to cross a small valley.)

RADium Descending Trail

Arriving at the trail fork at the top of U235. RADium is to the left.

RADium is a one-way downhill trail, reached by climbing up U235 and descending to the trail fork. A left turn here puts you onto RADium, which is the shorter of the two downhill options.

Like Yellowcake Walk, RADium is considered an easy ride and is suitable for less-skilled riders and bike trailers.

RADium is 1.7 miles long, dropping a bit over 300 feet. It contours a small valley midway between U235 and Yellowcake Walk. It ends at the four-way trail fork near the trailhead.

Like the other Mud Springs trails, RADium is machine-built with a very wide riding platform and highly-banked turns.

Contouring the hill on the way down.

View to the west. On the horizon are the sandstone bluffs of Behind the Rocks.

At mile 0.8 of the descent down RADium, you'll reach another trail fork. Keep left to descend RADium. A right turn takes you on Geiger Grind, where you'll hit Yellowcake Walk after 0.4 miles, then a primitive road that connects to camping areas in another 0.2 miles.

Yellowcake Walk Descending Trail

Rolling through a turn on the way down Yellowcake Walk.

Yellowcake Walk is the longer of the two downhill options. It's reached at mile 2.2 of U235, where a right turn at the trail fork takes you down Yellowcake Walk.

Yellowcake Walk is 2.7 miles in length. Because it starts and ends in the same place as RADium, it also has 320 vertical feet of elevation loss. But Yellowcake Walk has a couple of stretches of gentle climbing as it contours the north side of the hill, so your overall vertical will be greater with this option.

From the trailhead, a loop of U235 and Yellowcake Walk will be almost exactly 5 miles with 500 vertical feet of overall climbing.

Looking forward to a set of wiggles as the trail traverses the slope. On its lower half, Yellowcake Walk has some areas of gentle sustained uphill.

Flying down the wide riding path.

At mile 1.8 of Yellowcake Walk, you'll cross over Geiger Grind. Keep straight to continue descending Yellowcake Walk. A right turn downhill takes you to a doubletrack that connects to primitive camping. A left turn uphill will take you 0.4 to the lower portion of RADium.

At the bottom of Yellowcake Walk, you can continue straight ahead to make another climb up U235, or turn right to go back to parking.

Almost to the bottom as we roll past a rock outcrop.

Geiger Grind connector

We're standing on Geiger Grind, with my bike oriented along Yellowcake Walk. Straight ahead, just left of the sign, is the route to the dirt road.

Geiger Grind connects the lower portions of RADium and Yellowcake Walk. On RADium, the trail fork is at mile 0.8 from U235. A right turn here will take you 0.4 miles to Yellowcake Walk. If you continue across Yellowcake Walk, it's 0.2 miles to a dirt road. Here a left turn takes you out of the valley to some primitive camp spots north of the trailhead.

If you're on Yellowcake Walk, you'll hit Geiger Grind at mile 1.8 from U235. Here a left turn uphill takes you 0.4 miles to RADium, and again, the right turn drops 0.2 miles to the dirt road.

Looking south on Geiger Grind.

U235 to Yellowcake Walk

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Bottom Line

Half-way through a turn on the downhill, looking northeast.

The Mud Springs trail system is something that Moab has been lacking: a substantial set of flow trails. Granted, most of us come to Moab specifically for the brutal sandstone and dicey technical challenges. After all, we have flow trails close to home. But for kids and less-adventurous spouses, this system is a winner. And if you're ready for some laps of whoosh, this is the spot.

And remember, these trails are only open April 15 through November 30.

Map of Mud Springs

Area map.

Getting there: From the center of Moab, drive 11.9 miles south on US 191. Just after passing a large primitive parking area on your right, watch for a gravel road on your left. This is Yellow Circle Road, County Road 129. Drive 0.4 miles, keeping right as a gravel road joins. Turn right into the one-way parking strip.