Broad, but the hills close in again at Andernach, and this ravine-like part of its course cannot be considered as ending till below the Siebengebirge (Seven Mountains), where the river once more expands to a width of1300-1600ft.
HONNEF, a town and climatic health resort of Germany, beautifully situated on the right bank of the Rhine, at the foot of the Siebengebirge, 8 m.
Crowning the vine-clad hills behind it lie the ruins of the castle, a picturesque ivy-covered arch, whence a fine view is obtained of the Siebengebirge and the Rhine valley as far as Bonn.
"Der alte Zoll," commanding a magnificent view of the Siebengebirge, is the only remaining bulwark of the old fortifications, the Sterntor having been removed in order to open up better communication with the rapidly increasing western suburbs and the terminus of the light railway to Cologne.
The trachytes of the Siebengebirge are probably of slightly earlier date.
In the Siebengebirge the little crater of Roderberg, with its lavas and scoriae of leucite-basalt, is posterior to some of the Pleistocene river deposits.