HEI'DELBERG, an ancient city of Germany, in the grand duchy of Baden, is situated on the left bank of the river Neckar, in one of the most beautiful districts in the country, on a narrow- strip of ground between the river on the n., and the northern extremity of the Geisberg mountains on the south. It is 13 in. s.e. of Manheim, and about 54 in. s. of Frankfort-on-the-Main. The town consists mainly of one street about 3 in. in length. Among its most important buildings are the church of the Holy Ghost, through which a partition-wall has been run, and in which service according to the Catholic and Protestant rituals, is simultaneously carried on; the church of St. Peter's, on the door of which Jerome of Prague, the companion of Huss, nailed his celebrated theses, at the same time publicly expounding his dectiiiies before a Multitude asipmbled in the church yard; and the ruins of the castle, which was formerly the residence of the electors Palatine, and which, in 1764, was set on fire by lightning, and totally consumed. in the cellar under the castle is the famous Heidelberg tun, 36 ft. long and 24 ft. high, and capable of containing 800 Mids. Heidelberg is celebrated for its university, which, after those of Prague and Vienna, is the oldest in Germany. It was founded by the elector Rupreeht I. in 1386, and continued to flourish until the period of the thirty years' war,
when it began to decline. In 1802, however, when the town, with the surrounding territory, was assigned to the grand duke of Baden, a new era commenced for the university, and it rapidly became famous. It comprises faculties of theology, law, medicine, and philosophy, has 110 professors and lecturers, and is attended by from 600 to 800 students. Its library consists of about 300,000 volumes and 3,000 manuscripts. The trade and manufactures of the town are inconsiderable. Heidelberg, originally an appanage of the bishopric of Worms, became in 1155 the seat of the counts Palatine, and continued to be so for near six centuries. After the reformation Heidelberg was long the head-quarters of German Calvinism, and gave its name to a famous Calvinistic catechism. Heidelberg suffered much during the thirty years' war, was savagely treated by the French in 1688, and was in 1693 almost totally destroyed by them. Pop. '71, 19,988; '75, 22,335, of whom two-fifths are Catholics, and about 600 Jews.
As the residence of the rulers of the Palatinate, Heidelberg underwent all the vicissi tudes of that much-suffering electorate. See PALATINATE.