Dunes Drive is curvy in some areas so always use caution when driving and obey the speed limits. NPS Photo. Phone: Dunes Drive is an eight-mile (13 km) scenic drive that leads from the visitor center into the heart of the gypsum dunefield. The 16-mile (26km) round-trip drive takes approximately 45 minutes. However, you may want to allow additional time to explore the dunes, take photos, and/or learn about the natural and cultural history of the world's largest gypsum dunefield. Along the road, you will find outdoor exhibits, hiking trails, picnic areas, vault toilets, and parking areas.