The Protective Coastal Dune Ridge is one of the most distinctive parts of the Curonian Spit landscape. Stretching along nearly the entire length of the Curonian Spit's coastline (almost 100 km), this dune ridge protects the settlements of the spit from sea currents that bring in sand, which is later blown inland by the wind. The ridge prevents the drifting sand from moving toward the Curonian Lagoon. Near Smiltynė, its height reaches up to 14–15 meters above sea level.

The creation of the dune ridge began over 200 years ago through human effort. Using brushwood barriers and other reinforcements, people tried to stop the wind-driven sand from advancing deeper into the peninsula. Nature continued the work. The slopes of the ridge were planted with vegetation adapted to dry, quickly warming, nutrient-poor sandy soils and strong winds, such as beachgrass (Ammophila arenaria) and sand ryegrass (Leymus arenarius). The more these perennial grasses are buried by sand, the more they spread and the better they stabilize the dunes.