Dinosaur National Monument updates roads and campgrounds for spring visitors

Utah side is the easy win, but only if you know which loop to claim

Cub Creek Road is open on the Utah side, with the first 8 miles paved and the last 2 miles unpaved but still open, and Split Mountain Road is open as well. That means the quarry side of Dinosaur National Monument is very much in play for spring visitors, especially if your trip revolves around fossils, short hikes, or a camp night close to the monument’s core attractions. The catch is that the monument’s fossil showcase sits only on the Utah side, just north of Jensen, Utah, so this is the half of the park that matters most if your goal is to pair roadside access with the quarry experience.

Green River Campground is operating with flush toilets and drinking water, and it is still first-come, first-served through May 14 before shifting to a mix of first-come and reservation-only loops starting May 15. That setup matters because this is a practical base camp, not just a place to sleep: Green River Campground has 80 sites, no electric hookups, and sits about 5 miles from the dinosaur quarry and the Split Mountain Boat Ramp. If you are trying to stack a fossil stop with a river launch or a short, low-fuss overnight, this is the campground that makes the logistics work.

Split Mountain Campground is also open, but unlike Green River’s flexible spring rollout, it requires reservations through Recreation.gov. That makes it the cleaner choice if you want to lock in a spot before driving in, rather than gambling on a walk-up loop. The monument’s campground rules are worth reading like gear specs: prices vary by season and water availability, and generators are only allowed from 7:00 a.m. to 9:00 p.m., so this is not the place to assume full-service comfort just because the roads are open.

Colorado side is open too, but it is still the rougher half of the monument

Harpers Corner Road is paved and open, which gives the Colorado side a straightforward approach for visitors who want views without committing to backcountry driving. Echo Park Road and Yampa Bench Road are also open, but both are unpaved and recommended only for high-clearance 4WD. That distinction is not academic here. In Dinosaur, an “open road” can still be a road that punishes the wrong vehicle, the wrong tire choice, or the wrong weather window.

Echo Park Campground is open and has vault toilets and drinking water, so you can still build a serious Colorado-side overnight around it. But the road network feeding it is the real gatekeeper, especially if your plan includes remote canyons, river access, or a longer loop through the monument’s western country. If you are coming in a crossover or a low-clearance setup, Harpers Corner is the safer bet. If you are bringing a high-clearance rig and you know how to use it, Echo Park and Yampa Bench remain on the table.

Bull Canyon Trail is the one place where “open” would be the wrong word

Bull Canyon Trail is the clearest warning in the update. The trail is about 1.5 miles one way, steep, and unmaintained, and it drops from Yampa Bench Road to the Yampa River. It was previously damaged by flooding, with complete washout in sections of the lower canyon, so this is not a routine shoulder-season nuisance. This is the kind of damage that changes whether the hike is worth planning at all.

The road to the trail is part of the problem too. Yampa Bench Road is 18 miles one way, rugged, and typically impassable when wet, especially in winter and spring. Add the monument’s warning about bank collapse near Deerlodge Park and the fact that some remote zones have little to no cell service, and the message is blunt: the Colorado backcountry is still a place where route discipline matters more than ambition. If conditions look soft, slick, or uncertain, Bull Canyon is the first thing to trim from the itinerary.

Trails and backcountry access are still broad enough to build a real trip

The good news is that the monument’s trail list is largely open. Fossil Discovery Trail, Sound of Silence Trail, Desert Voices Trail, River Trail, Lizard Petroglyph Trail, Box Canyon Trail, and Hog Canyon Trail are all included in the current open slate, which gives you plenty of ways to keep a spring visit active without betting everything on the hardest routes. That mix is especially useful if you are traveling with people who want one easy hike, one fossil stop, and one scenic drive rather than a full-on expedition.

Backcountry and campground access are still a patchwork, but a usable one. All other campgrounds and backcountry areas are first-come, first-served except for specific reservable sites, including Green River Campground, Split Mountain Group Campground, the Echo Park group site, and Ely Creek on the Jones Hole Trail. If you prefer certainty, those reservable places are the ones to chase. If you prefer flexibility, the first-come system still gives you options, but only if you arrive with enough margin to adjust on the fly.

Why this update matters for a spring Dinosaur trip

This is still a big, two-state park spread across more than 210,000 acres, and the split between Utah and Colorado really does change the kind of trip you can pull off. Dinosaur National Monument also remains a serious river destination, with the Green and Yampa rivers driving rafting and boating traffic through the canyons, so road and campground status are not side notes. They determine whether you are setting up a quarry-and-river weekend, a Colorado-side backcountry run, or a simple overnight with a hard deadline on when to roll in.

The scale of the place has always made access the real story. In 2023, the monument drew 326,529 visitors who spent $24.12 million in nearby communities and supported 336 jobs, so when roads, camp loops, or trails shift, the impact reaches far beyond one trailhead. Recent construction-related closure history, including the Quarry Exhibit Hall shutdown tied to road, parking lot, and sidewalk reconstruction, is a reminder that this park often asks visitors to adapt even when it never fully closes.

For this spring, the read is straightforward. The Utah side gives you open roads, operating campgrounds, and quarry access. The Colorado side still rewards the right vehicle and punishes bad assumptions. If you plan around that split, Dinosaur is ready. If you do not, Bull Canyon and Yampa Bench will make the decision for you.