Great Sand Dunes is a truly unique national park, located north of Alamosa. The 150,000 acre park is a mixture of grasslands, wetlands, forests, lakes, high peaks and what it’s known for, sand dunes. The 30 square mile dunefield is the tallest and largest in North America, at 750 feet vertical.
Surrounding the park are the Sangre de Cristo Mountains. These snow capped peaks, fuel Medano and Sand Creeks which run seasonally at the base of the dunes.
Medano creek is one of the best places to see “surge flow”, where waves come in rhythmic, 15-second intervals due to sand buildup on the creek bed. Shortly after leaving the park the creek disappears into an underground aquifer. The creek is usually dry by the end of the summer.
How the dunes formed
Wind and water eroded the mountains and streams deposited sand onto the valley floor. Southwesterly winds then collected sand from across the San Luis Valley before being block by the Sangre de Cristo Mountains.
The sand was then dropped at the base of the mountains. Wind also came from the northeast reversing the wind flow and blowing sand back toward the Dune Field.
Backpacking, Camping, Hiking, Horseback Riding, Hunting, Picnicking, Sandboarding, Skiing & Sledding on the Dunes, 4WD Medano Pass Primitive Road, Swimming in Madano Creek, Visitor Center
Camping: Yes; they fill up quickly during peak season.
- Pinyon Flats Campground – Loop 1 (44 sites), first-come, first-served; Loop 2 (also 44 sites) and 3 other group sites are reservable.
- Medano Pass Primitive Road Campsites – Free, includes backpacking and car camping along the Medano Pass 4WD road, first-come-first-served. High-clearance 4WD is required for car camping along Medano Pass.
- Nearby Campgrounds (not in Park) – San Luis State Park; Zepata Falls; Great Sand Dunes Oasis is next door, greatdunes.com
- Sand Dunes – The 30 square-mile sand dunes are open for exploration. Hike anywhere you like. High Dune is the most popular and closest to Visitor Center. It’s a 650-foot vertical hike, which takes 2-3 hours round trip. It’s tough hiking in sand, much like snow. Star Dune is the highest at 750 feet vertical.
- Sand Sheet Loop Trail – An easy, 1/2 mile loop trail located just behind the Visitor Center. There are several informational plaques located around this 20 minute loop. Learn about the geology, plants, humans and animals of the San Luis Valley.
Horseback Riding: Permitted in park; leave trailer at Medano Pass Primitive Road. There are also 3 licensed providers of guided horseback trips who will meet you in the park with horses by reservation.
Hunting: Only permitted in the National Preserve during designated seasons, not in the National Park. See NPS hunting page (here).
- During summer sand gets very hot, up to 140°F. Hike in early morning or early evening. Dogs usually don’t last long on the sand dunes due to their paws getting hot.
- Take your time and drink plenty of water. Wear suncreen, sunglasses and a hat.
- Campsites fill up quickly during peak season. Reserve early or check out nearby campgrounds.
- Wear sneakers while hiking up the sand. Flip-flops or going bare-foot are bad choices.
- Bring lunch with you. The gift shop sells only a few snacks.
- Use a slick, rigid, flat sled on sand. Saucers won’t work.
Season: Year round, 24 hours a day
Fees: $3 per adult (16), good for 1 week
Pets: Yes, on-leash
Maps: Great Sand Dunes Visitor Guide (PDF)