LEYDEN (anc. Lugdunum Batavorum), a celebrated city of Holland, province of South Holland, on the Rhine, or rather on that branch of it that retains the name, 10 miles E.N.E. of the Hague, and 23 miles S.W. of Amsterdam, with both of which it is connected by railway. It is surrounded with a rampart, outside of which is a wet ditch crossed by eight bridges leading to as many gates. The River Rhine flows through the heart of the town; and, like other Dutch towns, Leyden is traversed by numerous canals which divide it into about fifty small islands communicating with each other by a great number of bridges. The streets are usually long, broad, and well paved; and the houses are generally of a superior class. The Breede Straat is nearly two miles in length, and is reckoned one of the finest streets in Europe. The town-hall is a picturesque old building, founded in 1574, and containing a valuable collection of paintings. St Peter's church, built in 1315, is the largest and finest in the city, and contains among its monuments one to the celebrated physician Boerhaave. The remains of a round tower, called the Burg, stand on a slight eminence in the centre of the town, and from the walk round the top the finest view of the city and neighbourhood is obtained. It is said by some to have been built by Drusus, though others ascribe it to Hengist about A.D. 450. Near the Burg stands the church of St Pancras, built in 1280, and containing the monument of the brave burgomaster Vanderwerff, who defended the city against the Spaniards in 1574. The University of Leyden, long one of the most distinguished seats of learning in Europe, was founded by the Prince of Orange in 1575, to reward the inhabitants for their bravery in defending the town against the Spaniards. Among its professors were Scaliger, Heinsius, Gomarus, Arminius, Boerhaave; and among its students Grotius, Descartes, Goldsmith, and Fielding. It has faculties of theology, law, medicine, science, and literature; and has usually from 600 to 700 students. It has also a valuable library, botanic garden, observatory, museums, &c. (See article HOLLAND.) There are likewise many fine private libraries and museums, among which may be mentioned the Japanese collection of Dr Siebold. The manufactures are unimportant, but it carries on some trade in grain, butter, and cheese. Historically, Leyden is chiefly noted for the gallant and successful defence made by the inhabitants in 1574 against the Spaniards under Valdez. The siege lasted for about five months, during which the inhabitants endured the greatest suffering from famine and pestilence. Pop. (1855) 37,029.