Volcanic ashes and lavas deposited during this period are still found in the Mendip Hills and in Pembrokeshire.
Volcanic deposits formed Ben Nevis in the Devonian Period.
During the Carboniferous Period, around 360 Ma, the UK was lying at the equator, covered by the warm shallow waters of the Rheic Ocean, during which time the Carboniferous limestone was deposited, still found in areas such as the Mendip Hills and the Pennines.
The coal measures were formed at this time, in river deltas, swamps and rain forests.
This gives rise to the wide variety of landscapes found across the UK.