On the surface it is obvious what makes Lanzarote a top holiday destination. The brilliant sunshine, sandy beaches, warm sea breezes, are all exactly what most holiday-goers look for in a getaway destination. However, Lanzarote’s beauty goes much further than its surface appeal. The Canary Islands’ most famous destination is also home to one of the most geologically fascinating phenomena, known as the Cueva de los Verdes.Magnificent CavesThe Cueva de los Verdes are a stunning and extensive underground volcanic labyrinth of tunnels found in the Monumento Natural del Malpais de La Corona, which is a protected natural area of the island. The caves were created over 3000 years ago by the lava flows that erupted from the Monte Corona volcano nearby. The caves delve deep under the island, extending over 6 kilometres above sea level and 1.5 kilometres below.In the 1960s, two kilometres of the cave system were secured and established as a tourist attraction. Today, they are even used as a concert hall that can seat up to 500 people.Visiting the CavesThe caves are open to the public during the summer from 10am to 7pm. This amazing geological spot is one of the most popular tourist attractions on the island and consequently can be very crowded. It is recommended to visit later in the afternoon after the crowds have subsided - especially during the summer season.Tours of the caves are available throughout the day and usually last about an hour. The guides are very knowledgeable and can explain all about the magnificent variations in colour found on the walls of the cave. The red colouration can be explained by oxidation and iron content, and the ochre shades are due to the reflection of the light on the salt deposits that coat sections of the caves’ interior, caused by the sea water seepage from the surface. Although each geological effect has a very scientific explanation, it does not detract from the sense of magic and mystery created by the caves.It is important to come prepared for a visit to the caves. A good pair of walking shoes with a decent tread is a must as there is a fair amount of stair climbing and uneven surfaces involved. Once inside, the caves’ certain sections can be quite narrow and tight and others require a climb. Previous visitors have also recommended bringing a bottle of water during your visit as the tunnels can become a bit hot and stuffy. However, the views and the chance to see the elusive albino crabs make all the effort very worthwhile!Getting to Your DestinationDue to Lanzarote’s popularity, flights are both frequent and affordable and go directly from London to the Lanzarote airport. Transfer from the airport to your hotel with an easily pre-booked shuttle and your holiday is off to a brilliant start! Enjoy both the beautiful surface and subterranean attractions the island has to offer.