Langwell Forest
Significance: an ancient inselberg landscape
Langwell Forest
Significance: an ancient inselberg landscape

Main image on top: Langwell Water and Morven mountain (Credit: mark ferguson / Alamy Stock Photo/2HBWGK5 )

Langwell Forest

Significance: an ancient inselberg landscape that draws the eye across the plain of Caithness

The spectacular scenery of the Langwell Forest is not primarily a result of glacial erosion. The inselbergs, ridges and valleys relate to much older terrain: the sub-Devonian surface and Tertiary erosion surfaces. The conglomerate hills are ornamented by wart-like tors.

Godard’s (1965) map of erosion surfaces in the Langwell Forest. 1. Faults 2. Break of slope at the edge of the quartzite. 3. Break of slope at the edge of Devonian conglomerates. 4. Sub-Devonian surface expressed as gentle slopes. 5. Sub-Devonian surface expressed as steep slopes. 6. Scottish Surface 7. Pliocene Level 8. Gorge.

The sub-Devonian landsurface has emerged from beneath its cover of Devonian breccia, conglomerate, and sandstone. Generally restricted in area, it nonetheless defines slopes of varying inclination that were eroded 380 million years ago and then buried beneath hundreds of metres of desert sand and gravel. The continuous northern face of Scaraben is one such ancient escarpment.

Cnoc na Feadaige

The main ridges are developed in resistant quartzite and form a striking Appalachian terrain. Later, low relief, erosion surfaces extend to the flanks of the ridges and record prolonged phases of erosion. The present elevation of the erosion surfaces reflects to the progressive uplift of the Northern Highlands over the last 60 million years.

Langwell Water

© Copyright Richard Webb (https://www.geograph.org.uk/photo/7457607)

Langwell Water

© Copyright Richard Webb (https://www.geograph.org.uk/photo/7457543)

Key geomorphological sites