Tags: Site Of Special Scientific Interest.
Garth Bank Quarry is a Site of Special Scientific Interest in Brecknock Powys Wales.The Countryside Council for Wales describes the significance of the quarry as follows:The rocks in this quarry are siltstones and pebbly sandstones of late Ordovician and early Silurian age approximately 440 to 445 million years old. The rocks provide an insight into the environmental conditions at the boundary between the Ordovician and Silurian Periods.