Sites on Loop 1 generally have less trees but more open views of the dunes and mountains. NPS/Patrick Myers. A few sites have driveways that can fit RVs up to 25 feet in length. Piñon Flats Campground - Great Sand Dunes National Park & Preserve (U.S. National Park Service) Some sites in Loop 1 and Loop 2 can accommodate RVs or camping trailers up to 35 feet in length. However, there are no electrical, sewer, or water hookups. A dump station and water hoses are available in warmer months near the campground. Drivers with RVs longer than 35 feet will find it difficult to turn corners or clear tree branches, and should consider other area campgrounds. RVs, trailers, and pop-ups will not fit and are not permitted in the group tent camping sites. Link to find driveway lengths for Loops 1 and 2 sites and make a reservation on recreation.gov. Please purchase firewood locally to prevent the import of forest pests from other regions.