SIEBENGEBIRGE (“The Seven Hills”), a cluster of hills in Germany, on the Rhine, 6 m. above Bonn. They are of volcanic origin, and form the north-western spurs of the Westerwald. In no part of the Rhine valley is the scenery more attractive; crag and forest, deep dells and gentle vine-clad slopes, ruined castles and extensive views over the broad Rhine and the plain beyond combine to render the Siebengebirge the most favourite tourist resort on the whole Rhine. The hills are as follows: the steep Drachenfels (1067 ft.), abutting on the Rhine and surmounted by the ruins of an old castle; immediately behind it, and connected by a narrow ridge, the Wolkenburg (1076 ft.); lying apart, and to the N. of these, the Petersberg (1096 ft.), with a pilgrimage chapel of St Peter; then, to the S. of these three, a chain of four — viz. the Ölberg (1522 ft.), the highest of the range; the Löwenburg (1506 ft.); the Lohrberg (1444 ft.), and, farthest away, the Nonnenstromberg (1107 ft.). At the foot of the Drachenfels, on the north side, lies the little town of Königswinter, whence a mountain railway ascends to the summit, and a similar railway runs up the Petersberg. The ruins which crown almost every hill are those of strongholds of the archbishops of Cologne and mostly date from the 12th century.
See von Dechen, Geognostischer Führer in das Siebengebirge (Bonn, 1861); von Stürtz, Führer durch das Siebengebirge (Bonn, 1893); Laspeyres, Das Siebengebirge am Rhein (Bonn, 1901).