Wiesbaden, a city of Prussia, in the province of Hesse-Nassau, formerly the capital of the duchy of Nassau, in the basin of the Salza, on the S. E. slope of the Taunus mountains, 20 m. W. by S. of Frankfort; pop. in 1871, 35,463, all Protestants excepting 7,000 Catholics and about 1,000 Jews. It is one of the great German watering places, and in 1875 was visited by 40,000 tourists and invalids. The Wilhelmsstrasse, half a mile long, lined with trees, leads from the railway, station to the Theaterplatz, with a beautiful theatre, opposite the Kursaal. The latter is a magnificent building on the E. side of a square, the N. and S. sides of which have covered colonnades with stores. It is the centre of attraction, and has ball, reading, dining, and concert rooms, a splendid parlor surrounded by marble pillars, extensive pleasure grounds,' and an arcade of iron and glass (the Frinkhalle), which connects the grounds with the Kochbrunnen. This is the principal boiling spring (about 156° F.), yielding 17 cub. ft. of water per minute. The next hottest and largest spring is the Adlerbrunnen in the Adler hotel (about 144° F.), and there are many other springs used for drinking and bathing.

There are also watercure, orthopedic, gymnastic, and other establishments, and about 30 bathing houses with over 800 separate rooms. The heat in summer is oppressive; the season extends to autumn, when the weather is delightful. The vicinity of the Rhine and of Frankfort and Homburg makes it a favorite resort for excursionists, especially on Sundays; on week days it has a monotonous and hospital-like appearance. Wiesbaden has a splendid Protestant church, built in 1853, a Catholic church with three large naves and fine altarpieces, finished in 1849; a royal (formerly ducal) and other palaces, the art union gallery, a library of 70,000 volumes, and a museum of antiquities and natural history; and in the vicinity are Fresenius's chemical laboratory, an agricultural institute, and a Greek chapel with gilded cupolas. The once excessive rouge-et-noir and faro gambling was restricted in 1862, and altogether abolished in 1872. - Like many other places containing thermal springs, Wiesbaden was a Roman military station. Under the Carlovingians a royal residence existed here under the name of Wisibad, and Otho I. raised the place to the rank of a town. Remains of a.

Roman castle were found in 1838, and of baths and a temple in 1867-'8. - The district of Wiesbaden (pop. about 600,000) includes most of the former duchy of Nassau, the landgraviate of Homburg, and the territory of Frankfort.