Antek Marciniec holds onto a slackline after falling off as he highlines between two cliffs at Diamond Bay on December 21, 2014 in Sydney, Australia. Slacklining is a balance sport in which participants walk on a flat nylon webbing anchored between two points with the tension adjusted to allow for slack, providing an experience similiar to that of walking on a trapmoline. Highlining is a style of slacklining where the two anchor points are set up with significant elevation from the ground or water. (Photo by Cameron Spencer/Getty Images)

Descending into the Marum Volcano in Vanuatu, Intrepid explorers found an unusual way of staying warm this winter by spending Christmas day on an active volcano. British climber Chris Horsley, 22, and his friends Gareth Hawken, 30, Geoff Mackley, 50, and Bradley Ambrose, 36, from Auckland, New Zealand, hiked up the Marum Volcano, Vanuatu, on the morning of the 25th. Instead of passing the day with their families, the team climbed down a 1200ft cliff to get close to a flowing lake of lava. (Photo by Bradley Ambrose/Caters News)

Vardzia is a cave monastery site in southern Georgia, excavated from the slopes of the Erusheti Mountain on the left bank of the Mtkvari River, thirty kilometres from Aspindza. The main period of construction was the second half of the twelfth century. The caves stretch along the cliff for some five hundred metres and in up to nineteen tiers. The Church of the Dormition, dating to the 1180s during the golden age of Tamar and Rustaveli, has an important series of wall paintings. The site was largely abandoned after the Ottoman takeover in the sixteenth century. Now part of a state heritage reserve, the extended area of Vardzia-Khertvisi has been submitted for future inscription on the UNESCO World Heritage List

Michael Hughes creates cool optical illusions by placing cheap souvenirs in front of famous landmarks. Michael has discovered the technique back in 1998 when he held up a postcard he bought for his daughter on the tourist platform at the Lorelei cliffs next to the river Rhine. “I was amazed because it just seemed to fill a massive grey hole that was in the sky and it was the exact position the photographer had taken the picture from,” said Michael to Daily Mail.

Located at La Casa Del Arbol or “The Treehouse” in Baños, Ecuador, this small house was built for the stunning view on the Tungurahua Volcano it offers. But the real attraction is the swing attached to one of the tree's branches. It is far from your average swing, and it is surnamed the "Swing at the End of the World" for a good reason. Located off a giant cliff at over 2,600 meters above sea level and with absolutely no safety features, this swing promises a serious thrill to whoever is brave enough to ride it.

Ronda is a small Spanish town that it well known by many people around the world. It became a popular tourist destination due to its peculiar location. Some of its buildings are standing right next to the large cliff drop, making for a very scary sight, especially if you were to look down through one of their windows unaware of what kind of sight awaits you. If you ever find yourself looking for this ancient town, you can travel to it from Costa del Sol or Malaga. In the past, this town played a major strategic role due to its high elevation, which made defending it from invaders a lot easier.

The Haʻikū Stairs, also known as the Stairway to Heaven or Haʻikū Ladder, is a steep hiking trail on the island of Oʻahu. The trail began as a wooden ladder spiked to the cliff on the south side of the Haʻikū Valley. It was installed in 1942 to enable antenna cables to be strung from one side of the cliffs above Haʻikū Valley to the other. A building to provide a continuous communication link between Wahiawā and Haʻikū Valley Naval Radio Station was constructed at the peak of Puʻukeahiakahoe, elevation about 2,800 feet (850 m). The antennae transmitted very low frequency radio signals from a 200,000-watt Alexanderson alternator in the center of Haʻikū valley. The signals could reach US Navy submarines as far away as Tokyo Bay while the submarines were submerged.