The Siebengebirge is a low mountain range on the right bank of the Rhine, southeast of Bonn, in the eastern urban area of the cities of Königswinter and Bad Honnef, which consists of more than 50 mountains and hills.
It is of volcanic origin and formed about 25.5 million years ago in the Oligocene.
The last volcanic activity occurred in the Miocene and led to the formation of Petersberg.
The Siebengebirge is entirely part of the Siebengebirge Nature Park, one of the oldest nature parks in Germany.
The protection is regulated in a specific set of rules.
The Siebengebirge nature reserve with even stricter protection regulations is somewhat narrower, but contains the entire Siebengebirge in addition to the western part of the Ennert bordering the north and the northern half of the Rheinwesterwälder volcanic ridge adjoining the mountains in the south.
It is the largest contiguous nature reserve in North Rhine-Westphalia.
The Siebengebirge was included in the list of 77 awarded national geotopes in 2006.
Since the dissolution of main group 325 Rheinwesterwald in 1960, the Siebengebirge has been counted as part of the Middle Rhine region (Lower Middle Rhine region) in the handbook of the natural spatial structure of Germany.
(Source: Wikipedia)