Last updated on August 31, 2019
The development of cave systems means large amounts of limestone rock is removed from a landscape. Underground cavities are enlarged rock falls and form caves.
The gradual weathering of limestone rock by acidic water can create incredible cave systems. Over thousands of years, small caves steadily grow, creating huge caverns, while small cracks in the rock become large tunnels. When this lineup, huge interlinked networks are created, filled with thousands of stalactites. With the right safety equipment, these caves can be an exciting environment for people to explore.\
Tham Hinboum cave in Laos has the worlds longest navigable underground river- it is over 7 km(4.5 miles) long.