The Naglių Nature Reserve occupies an area of 1680 hectares. It extends for the distance of 9 kilometres from Juodkrantė to Pervalka. Here you can see the so called Grey Dunes (Lith. Pilkosios kopos), otherwise known as the Dead Dunes (Lith. Mirusios kopos), spontaneous wild-growing forest vegetation and centennial wood soils buried underneath the sand. Due to strong winds impressive ravines, erosions and washouts are formed in these dunes. Here and there, fragments of old soils appear from under the sands. Sightseeing of the nature reserve and the scenery of the Grey Dunes is allowed on the 31st kilometre of the road Smiltynė – Nida, where a parking lot is equipped for this purpose and there built a special sightseeing path in the area. Its length is 1100 m. Half of that distance is covered with gravel or boardway, the rest is sand.