Covering an area of 18 thousand hectares, the Kursiu Nerija National Park was designated to protect the unique scenic beauty of the Kursiu Nerija, a narrow peninsula separating the Kursiu Marios (Curonian Lagoon) from the Baltic Sea. The peninsula, a sandy stretch of land extending 98 kilometers, with the width varying from 400 meters to 3.8 kilometers, was formed some five to six thousand years ago, as sand accumulated in the shallower waters along the Baltic coast.

The sea winds shifted the sand, creating a range of large sand dunes stretching for about 70 kilometers from Smiltyne to Sarkuva. The largest of the dunes, such as the Sklandytoju, the Angiu Kalno, and the Urbo Kalno ones are up to 1000 meters high and provide a charming view of the sea, the lagoon and the green forests.

Up to the 15th century the spit was covered by both deciduous and coniferous forests. Later, however, large portions of them were felled by the axe. This lead to severe sand shifting. 14 villages were swallowed up by the moving sands. It was in 1825 that G.D. Kuvertas started the first reforestation project to try to stop the sand. At the present time life on the spit is protected by about 7 thousand hectares of forests, most of them pine-woods.

The settlements situated on the spit boast of original architecture, typical to this region. In Juodkrante, the first stop on the road from the northern tip Nida, the peninsula's administrative centre, one can see a number of old fishermen's houses that are protected as architectural monuments. The other settlements before Nida are Pervalka and Preila, typical fishing villages. Nida is the largest and most beautiful of the Lithuanian settlements on the spit. 37 rare plant species grow on the spit. Some of them are listed in the Red Book of Lithuania: Eryngium maritimum, Glaux maritina, Aster tripolium and Erica tetralix. Kursiu Nerija has 2.600 residents. All settlements contain etnographic architectural monuments, the old part of Nida has been pronounced an urbanistic monument.

The Kursiu Nerija National Park stands out among the other parks of Lithuania. Because of ecological concerns, access to the spit is restricted. Visitors can obtain information and book a guided tour of the park in Klaipeda.