Читать книгу Cycling in the Cotswolds. 21 half and full-day cycle routes, and a 4-day 200km Tour of the Cotswolds онлайн

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The clay rocks are known as ‘Lias’ – a term invented by 18th-century quarry workers to describe the layered rock, and adopted by William Smith, a canal-building engineer who went on to become the ‘Father of Geology’ (See Route 9 for more on William Smith). The limestone is Oolitic – where the regular structure of spherical crystals looks like a collection of eggs. This is divided into two groups: Inferior Oolites are the older of the two, and tend to be found on the scarp slopes of the northwest Cotswolds; Greater Oolites are more typically found on the gentler slopes outside the north west, and form the region’s traditional honey-coloured building limestone, the colour being typically more pronounced towards the north of the region. Its evenness of grain (enabling it to be cut in any direction) and durability made it the preferred building stone for many prestigious buildings, such as St Paul’s Cathedral.

Glacial and post-glacial meltwater rivers have also contributed to the sometimes surprisingly hilly nature of the Cotswolds – with the Stroud valleys (Routes 19 and 22) being good examples of deeply-incised river valleys in the region.