Vogelsberg


The Vogelsberg is a large volcanic mountain range in the German Central Uplands in the state of Hesse, separated from the Rhön Mountains by the Fulda river valley.
Emerging approximately 19 million years ago, the Vogelsberg is Central Europe's largest basalt formation, consisting of a multitude of layers that descend from their peak in ring-shaped terraces to the base.
Image:Hoherodskopf Vogelsberg.jpg|thumb|Hoherodskopf
Image:Taufstein Bismarckturm.jpg|thumb|right|upright|Bismarck tower on the Taufstein
The main peaks of the Vogelsberg are the Taufstein,, and Hoherodskopf,, both now within the High Vogelsberg Nature Park.

Location

The Vogelsberg lies in the county of Vogelsbergkreis, around 60 kilometres northeast of Frankfurt between the towns of Alsfeld, Fulda, Büdingen and Nidda. To the northeast is the Knüll, to the east the Rhön, to the southeast the Spessart and to the southwest the low-lying Wetterau, which transitions to the South Hessian lowlands of the Rhine-Main region. In the opposite direction, to the northwest, the Vogelsberg transitions into parts of the West Hesse Highlands, whilst retaining the name, Vogelsberg, and the basalt rocks that bear its name continue well beyond the actual Vogelsberg.

Geology

The Vogelsberg is the largest contiguous volcanic region in Central Europe with an area of 2,500 square kilometres. It is not a former shield volcano, but comprises many individual volcanoes, which are superimposed. Thus it consists of a multitude of overlapping basalt terraces, which descend from the Oberwald, the high central plateau, 600 to 773 metres high, in series of stepped rings to the edges of the mountain region. Its present appearance, which is reminiscent of a large flat, shield-shaped volcano with a central dome, is the result of an interplay of uplift processes and ablation acting on all sides.
The volcanic activity in the Vogelsberg, as well as that of the North Hessian Volcanic Region to the north which extends as far as Adelebsen in Lower Saxony, is connected with fault block activity that, during the Tertiary, led to the formation of the Lower Hessian Basin. It began in North Hesse about 20 million years ago during the lower Miocene, reached a peak about 13-12 million years ago and came to an end about 7 million years ago, during the upper Miocene. The volcanism of the Vogelsberg was mainly active during the Middle Miocene, according to potassium-argon dating 18.5-10 million years ago, reaching its peak 17-15 million years ago.
As a result of volcanic activity, mainly basaltic lava and pyroclastic deposits were formed. During the course of this volcanicity, trachyte and phonolite were produced in the early stages, then alkali-olivine basalts were deposited, which alternated with tholeiites. These volcanic products overlaid a basement of bunter sandstone and tertiary sands, in small areas in the east also rocks of the muschelkalk and keuper.
Erosion following the Miocene wore away the contiguous basalt nappes, which originally reached as far as the area of the Lower Main, back to isolated deposits in the central complex. Under tropical to subtropical conditions, the volcanic rocks were turned into red clays by lateritic weathering. In many places, red clays collected and bauxite was formed; moreover, the iron contained in basalt was concentrated to form iron ore. These deposits were mined over a long period of time in order to produce raw materials for industry, and the basalt was and still is a highly popular raw material for gravel and natural stone production.

Natural region divisions

The division of the Vogelsberg into individual natural regions is based, on the one hand, on the relief of the mountain range from its highest point towards the outside and, on the other hand, on its river catchments which radiate outwards: the catchments of the Eder, Lower Fulda, Main and Lahn.
The following natural regions form the Vogelsberg:
  • 350 Lower Vogelsberg
  • * 350.1 Northern Lower Vogelsberg
  • * 350.2 Northwestern Lower Vogelsberg
  • * 350.3 Eastern Lower Vogelsberg
  • * 350.4 Western Lower Vogelsberg
  • * 350.5 Southern Lower Vogelsberg
  • * 350.6 Giesel Forest
  • 351 High Vogelsberg
  • * 351.0 Western High Vogelsberg
  • * 351.1 Eastern High Vogelsberg
  • * 351.2 Oberwald
Soils and rocks are, in all parts of the Vogelsberg – with the exception of the Giesel Forest – similar, but average annual temperatures drop noticeably towards the centre of the range and the annual precipitation rises towards the Oberwald to an average of 1,200 mm.
The basalt areas of the Vogelsberg continue towards the east and north into its neighbouring natural regions, whilst the Giesel Forest in the east is already on bunter sandstone, like the rest of the natural regions towards the east.
The Vogelsberg massif has stone runs of basalt and tuff, raised bogs and areas of ancient woodland. Numerous hiking trails cross, not only the Oberwald, but also the rest of the area.

Oberwald

The Oberwald is the heart of the Vogelsberg and is entirely wooded; its outer boundary roughly follows the 600 metre contour line. In outer areas of the Vogelsberg, by contrast, there is a tapestry of green pasture, arable fields and woodlands.
Large parts of the Oberwald are protected. For example, the beech wood in the Taufstein Nature Reserve has been left to manage itself since 1906.
On the northern slopes of the Taufstein are large stone runs of basalt.

Outer High Vogelsberg

The valleys of the Western and Eastern High Vogelsberg generally lie at heights of over 500 m in the north. In the west, some descend to under 400 m. In the main, the boundaries follow the watersheds of the source region of the most important rivers and especially that of the Rhine-Weser watershed, which runs from southeast to northwest, and the Lahn-Main watershed which heads east.
Because large areas of the original forest were cleared and the precipitation exceeds 1,000 mm per year, snow melt starts early. This and the less porous basalt loam soil frequently leads to flooding.
In this part of the Vogelsberg, the scenery changes in loose succession from woodlands, rich in springs, wetlands, poor grassland and stream valleys; besides there are also a raised bog and, in the southeast a number of waterbodies, the Vogelsberg Lakes.

Lower Vogelsberg (excluding the Giesel Forest)

The basaltic parts of the Lower Vogelsberg range in height between 300 and 500 m, except on the western to southwestern fringes by the Wetterau where they descend below 200 m in places.
Its boundary with the Büdingen Forest to the south, with the Landrücken to the southeast and with the Giesel Forest to the east is less of a relief feature than the geological transition from basalt to bunter sandstone.
There is also this geological divide with the Fulda-Haune Tableland, which lies in front of the Knüll to the northeast. Between them is the Großenlüder-Lauterbacher Graben. By contrast, in the north, the vulcanite does not end until it reaches the adjacent North Vogelsberg Foreland, i.e. outside the actual Vogelsberg. Even the Anterior Vogelsberg which lies outside the latter region still has large areas of basaltic rock. To the west the basalt zone reaches far into the gently rolling lowlands of the Wetterau, this depression lies alongside the middle and lower reaches of the Horloff river.
From a natural landscape perspective, the region is an island of forest comprising melic grasses and beech.

Giesel Forest

In the Giesel Forest, which covers an area of 130 km2, the Vogelsberg pushes eastwards at heights of up to over 500 m to the edge of the
Fulda Basin. From a natural region perspective, the only bunter sandstone part of the Vogelsberg is clearly separated from the basaltic areas of the Lower Vogelsberg.
In addition to the woods that cover almost the entire natural region there are extensive vegetation-free areas by the huge spoil tips of the potassium salt mine near Neuhof.

Table of natural regions (with high points)

The following table lists the natural regions from the centre outwards and then in clockwise order.
Designated
number
NameArea

Rivers
High points
with metres above sea level
351.2Oberwald37.02Only the rivers rising in the centre:
  • Taufstein
  • Hoherodskopf
  • Sieben Ahorn
  • Herchenhainer Höhe
  • Geiselstein
  • Nesselberg
  • Bilstein
  • 351.1EasternHigh Vogelsberg153.72
  • Völzberger Köpfchen, Rhine-Weser watershed
  • Naxburg, Rhine-Weser watershed
  • Horst
  • 351.0WesternHigh Vogelsberg136.47
    • Nidda
    • * Nidda
    • * Horloff
    • * Wetter
    • Ohm
  • Eckmannshain
  • Schlossberg and Ulrichstein Castle
  • Vogelsberg
  • Goldner Steinrück
  • 350.5SouthernLower Vogelsberg259.32
    • Kinzig
    • * Steinebach
    • * Ulmbach
    • * Salz
    • * Bracht
    • Nidda
    • * only Seemenbach
  • Wernerstein
  • Apfelberg
  • Galgenberg, western boundary with the Western Lower Vogelsberg
  • Katzenstein, southern boundary with the Büdingen Forest
  • 350.4WesternLower Vogelsberg387.72
    • Nidda
    • * Nidder
    • * Nidda
    • * Horloff
    • * Wetter
  • Galgenberg, eastern boundary with the Southern Lower Vogelsberg
  • Lehnkopf
  • Eschberg
  • Steigbügel, western boundary with the Wetterau
  • Hubberg, western boundary with the Wetterau
  • Steinknorre, eastern boundary with the Büdingen Forest in the extreme south
  • 350.2NorthwesternLower Vogelsberg154.63
    • Ohm
  • Bildsteinskopf, eastern boundary with the Northern Lower Vogelsberg
  • Bildstein
  • Kretenberg, northern boundary with the Northern Vogelsberg Foreland, Rhine-Weser watershed
  • 350.1NorthernLower Vogelsberg69.61
  • Bildsteinskopf, western boundary with the Northwestern Lower Vogelsberg
  • Baumgartskopf, northern boundary with the West Hesse Depression
  • 350.3EasternLower Vogelsberg245.32
    • Lower Fulda
    • * Schlitz
    • * Lüder
    • * Fliede
    • **
  • Mühlberg
  • Heerhain
  • 350.6Giesel Forest128.96
  • Lower Fulda
  • * Lüder
  • * Giesel
  • * Fliede
  • Knöschen, boundary with the Eastern Lower Vogelsberg on the southeastern edge of the forest
  • Himmelsberg