Curonian Spit National Park covers the Russian-owned southern 41 km of the 98 km long, curved Curonian Spit – a type of depositional sandbar. The spit separates the salt-water Baltic Sea from the freshwater Curonian Lagoon to the east. The southern portion of the spit lies within Zelenogradsky District in Kaliningrad Oblast, Russia; the northern portion lies within southwestern Lithuania. It is a UNESCO World Heritage Site shared by the two countries.