Building stone and Devon’s geology

Building stones of County Hall: A trail through geological time

In 1998, County Hall was listed Grade II* and in the listing notice it was highlighted that the building was constructed with quality materials.

Evidence of environments which are millions of years old can be seen in the stones which construct County Hall. You can find fossils and clues which indicate the setting which the rocks were formed in.

Two trail guides lead you to some of the best examples of attractive building stones on site and explain the geology behind the materials:

Access to County Hall and around the trail

The trail is only suitable for staff at County Hall and their visitors with planned visits. The trail around County Hall is all on the first floor except at stage 9, at the Grand Stairs. To access this point there is a lift available, which can be found behind the large granite commemorative stone highlighted in stage 8 of the trail.

Exeter Cathedral’s geology

Exeter Cathedral is magnificent and some have claimed that it possesses the most varied geology of any British cathedral. Materials from over 20 different quarries, many of them local, were used in its construction. The outer and inner Cathedral walls are made of Salcombe Stone, a sandstone quarried from Salcombe Regis in East Devon. Between these walls is a loose filling of the same volcanic trap (lava) quarried two miles west of the river Exe, also used in the construction of the City walls. Chalk mines at Beer, on the east coast of Devon, were worked to provide stone for use in some of the Cathedral’s sculptures. These sculptures can be seen on the impressive image screen at the front of the building.

More local geology can be seen inside the Cathedral. For example, the pillars supporting the Patteson Pulpit are made of a Devonian limestone and these can take a polish. This rock has been deformed by the earth’s movements, such that some of the corals within it appear elongated. It can be found at a number of sites in south west Devon. Follow a geology trail around the cathedral in the information leaflet Geology of Exeter Cathedral.

Exeter Cathedral