Caves to explore in United Kingdom
The United Kingdom consists of four constituent countries: England, Scotland, Wales, and Northern Ireland. It is the sixth-largest economy by nominal GDP and ninth-largest economy by purchasing power parity. It has a high-income economy and has a very high Human Development Index rating, ranking 14th in the world. It was the world's first industrialised country and the world's foremost power during the 19th and early 20th centuries.
Smoo Cave is a large combined sea cave and freshwater cave. The cave was formed along two geological lines of weakness by a combination of erosion from the sea and an inland underground stream which has formed the innermost chambers. The cave can be thought of as two caves formed by different mechanisms which have joined together over time.