Читать книгу Walking in the Pentland Hills. 30 walks in Edinburgh's local hills онлайн

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Route description

The main route description describes the ground covered, and has been thoroughly tried and tested. The numbered paragraphs correspond to the numbers along the line of the route on the map. (Be aware that things can change, however – trees are felled, footbridges become unsafe, and land management is ongoing – so be prepared for discrepancies between the route description and what you encounter on the ground.)

Geology and landscape

The Pentlands landscape owes its distinctive profile to the hardness of the 400-million-year-old volcanic rock, lava and ash of the Devonian period.

The heart of the Pentlands is formed from the folded sedimentary rocks of the Silurian age (435 million years), mainly marine shales and sandstones. This core is only exposed at three places: North Esk, Green Cleuch (Walk 8) and Loganlea. But it is the rocks of the succeeding Old Red Sandstone period (400 to 350 million years old) that have contributed to the form of the Pentlands we see today. After a period of erosion, coarse conglomerates and sandstones were laid down, and at this time volcanic activity also increased, and lavas and tuffs (volcanic ash) were deposited.