Ruciane-Nida is a town in Pisz County, Warmian-Masurian Voivodeship, Poland, with 4,934 inhabitants (2004). The town was formed in 1966 by the merger of three smaller settlements: Ruciane (German: Rudczanny, renamed Niedersee in 1938), Nida (German: Nieden), and Wola Ratajowa.