Jelenia Góra, city, Dolnośląskie województwo (province), southwestern Poland. It lies in the Sudeten (Sudety) mountains near the Czech border, at the confluence of the Bóbr and Kamienna rivers.
Archaeological data indicate that the site was occupied by an ancient Slavic tribe. Permanent settlement was begun in the 11th century by Jelnik, a knight who built the castle Nowy Dwór. The surrounding settlement was known as Jelenia Góra. The town reached its economic zenith, mainly because of its weaving industry, in the 15th and 16th centuries but was devastated by the Thirty Years’ War (1618–48) and, in 1640, by the plague. Rebuilt, it became the Baroque showplace of Silesia, only to wither again under 18th-century Prussian domination. Railroads made it a popular Silesian tourist centre in the 19th century, and interest in the nearby Karkonosze (Giant) mountain range as a resort area again revitalized the town in the second half of the 20th century.
The modern city has cellulose and synthetic-fibre industries, engineering facilities, and timber production, as well as its traditional textile industry. There are also pharmaceutical, optical, and clothing factories. Parts of the town walls (built 13th and 16th centuries) remain, as does a 14th-century parish church. Pop. (2011) 83,860.