SOPRON (Ger. Oedenburg; Med. Lat. Sopronium), a town of Hungary, capital of the county of the same name, 140 m. W. of Budapest by rail. Pop. (1900), 30,628, about 60% Germans. It lies in an extensive valley enclosed on all sides by the outskirts of the Rosalien mountains, a group belonging to the eastern outliers of the Alps. In the principal square are the Benedictine church, built at the end of the 13th century and restored in the 15th century, and the town hall, completed in 1894. The Dominican church, built in 1674; the church of St Michael, in the Gothic style, completed in 1484, the most interesting church in the town; and the old tower, 200 ft. high, are all worth notice. Sopron has a thriving industry in sugar, soap, vinegar, bell-founding and machinery, and it carries on an active trade in cereals, fruit and wine. Large cattle markets are also held here. Within the county a good quality of wine is produced, especially near the little town of Ruszt (pop. 1608) and at the village of Balf (Ger., Wolfs) on the shores of the Neusiedler lake. In the neighbourhood of Sopron is the Brennberg, with extensive coal-mines. Sopron was a Roman colony under the name of Scarabantia. It was afterwards occupied by German settlers and became a royal free town in the 11th century. Matthias Corvinus granted the town special privileges in 1464. An important Diet of Hungarian Protestants took place here in 1681.
About 12 m. north, at the foot of the Leitha mountains, lies the town of Kismarton (Ger. Eisenstadt; pop., 2951), which contains a magnificent castle of the Esterhazy family, built in 1683 and enlarged in 1805. About 10 m. north-west lies Nagymarton (Ger. Mattersdorf; pop., 3789); and not far from it, on the frontier of Austria, the well-preserved castle of Forchtenstein, the cradle of the Esterhazy family. About 12 m. east, not far from the Neusiedler lake, lies Esterhaza, with a beautiful castle in the French Renaissance style, belonging to Count Esterhazy. About 9 m. south-east lies the village of Nagyczenk (Ger. Zinkendorff), with the castle of the Szechenyi family.