About to enter the slab rock path through huge boulders of basault. Checkout rid...
About to enter the slab rock path through huge boulders of basault. Checkout ride (done as part of an official trail workday) December 2nd, 2017 by Bruce.
Boulder Dash

The Boulder Dash trail is a short double-black diamond expert trail in the Iron Hills trail system at Cedar City. Boulder Dash is one-way downhill. It begins near the bottom of the Green Hollow trail and descends to the one-way Lava Flow trail. It can be reached from above via the Greens Lake trailhead and Green Hollow, or from the bottom by climbing Lichen It then turning uphill on Green Hollow.

In addition to technical challenges, Boulder Dash shortcuts the downhill route from the Greens Lake trailhead. (After reaching Lichen It on Green Hollow, Lava Flow climbs uphill a bit. Boulder Dash bypasses the bottom of Green Hollow and the first part of Lava Flow.) The trail is 0.7 miles long with 200 vertical feet of elevation loss.
As a comparison, the route via Green Hollow and back uphill on Lava Flow is 0.4 miles longer, adding about 70 vertical feet of climbing. Not a big deal if you're not looking forward to tech stuff on Boulder Dash.
Looking back uphill at one of the steep ramps youll need to roll.
Looking back uphill at one of the steep ramps you'll need to roll.
Just getting started, heading south. The trail here could fool you. Its for expe...
Just getting started, heading south. The trail here could fool you. It's for experts: double black.
If you're planning to do Boulder Dash as part of a loop ride from the bottom, ride Lichen It then turn left uphill on Green Hollow. You'll find the trail fork on your right exactly 0.8 miles uphill from the origin of Green Hollow. Once you make a hairpin left turn, pedal 150 yards further and watch for the trail on the crest of a hill before Green Hollow drops through a shallow wash. The coordinates are N37 38.133 W113 04.489.
When heading downhill on Green Hollow, Boulder Dash is on your left at mile 1.7 from the Greens Lake trailhead parking lot. The fork comes just after you turn right in a drainage and climb a small hill. If you reach a 180-degree hairpin turn to the right, you went 150 yards past the trail fork and you'll need to backtrack.
Rocking and rolling through pinion and juniper.
Rocking and rolling through pinion and juniper.
There are only a couple of spots on the trail where you can take in a view. This...
There are only a couple of spots on the trail where you can take in a view. This big rock to the right of the trail is the best. Stop here.
The trail is hand-cut, so it's narrow and wiggly. (The work was done by volunteers through Dixie Mountain Bike Trails Association, a chapter of IMBA.) While the first bit seems reassuringly tame, you'll quickly find yourself banging over rocks on narrow trail hugging a steep side-slope. If you "walked" anything -- anything -- on Lava Flow because it made you nervous, you shouldn't go on this trail.
There's a lot of boulder rollovers, plenty of pedal-banging navigation through rocks, and some drops off boulders. There are several steep but short descents on dirt. A couple of them are slippery-slide loose -- and end in a quick check-and-turn to avoid flying off the mountain. Seriously, experts only.
Most of the trail has rock-work to support the outside edge, because it hugs a v...
Most of the trail has rock-work to support the outside edge, because it hugs a very steep side-slope.
Looking down the hill. Ive marked the path your bike will take.
Looking down the hill. I've marked the path your bike will take.
The highlight of this trail: over 100 feet of continuous rock-slab riding. This path is the most impressive rock work I've seen anywhere. A photo can't do it justice.
The rock slab path comes at mile 0.45. And although it looks intimidating, it's very rideable. Just keep your weight back and keep the bike moving at a reasonable pace so you don't hang up on a crack. On the other hand, don't hit it at full boogie either. There's a lot of bouncing that can easily send you into the big stuff along the side.
Bottom Line!
Short, but packed with challenges. If you're a true expert rider, it's worth extending your Lichen It to Lava Flow loop to add Boulder Dash.
Handlebar view south. Coming up: a steep drop as we hit the end of the rock path...
Handlebar view south. Coming up: a steep drop as we hit the end of the rock pathway.
map
Map of the Iron Hills system
Getting there, Southview:
At the southern I-15 Cedar City exit (Exit 57 to Cross Hollow Road and Highway 130), turn east onto Highway 130. Immediately turn right (south) from 130 onto Old Highway 91. Drive 0.3 miles. Watch for the sign for Southview Trailhead and turn left on Shurtz Canyon Drive. Now stay on Shurtz Canyon Drive to the trailhead and find a spot to park. The Lichen It Trail is to the east (uphill) from where you entered the parking lot. 
Greens Lake:
On Old 91 as above, at mile 0.1 turn left on Greens Lake Drive. Keep going uphill after the road turns to gravel. The trail head is on your right, about 2.3 miles uphill from 91.

Bathrooms:  Southview Trailhead
Water:  None at trailhead
Camping:  None at trailhead

GPS track files (right-click and "Save as..."):
     GPX LichenIt/GreenHollow climb
     Boulder Dash Trail only
      Multi-track area files
Topo map for printing:    View high-res topo
Lodging, camping, shops:     Links to Cedar City area resources