Top 10 Amazing Hidden Places That You Can Visit

Located in the county of Kent, England, this medieval castle’s origins date back to the 11th century. The largest castle in England has had many uses, and additions added on over the years. Some have even been added under. While castle tunnels aren’t necessarily unique – Canada’s Casa Loma also boasts tunnels, for example - Dover Castle’s tunnels have taken on many roles. The tunnels beneath the castle were first used as barracks, and could be occupied by more than 2000 men. During WWII, they were converted into air raid shelters, command centers, and even a hospital. The castle is open for tours, and the tunnels are available to explore.

Underneath the Santa Maria della Concezione dei Cappuccini church in Rome are several small chapels. This is not so unusual; the remarkable thing is what they are decorated in: the bones of over 3700 bodies. Located in the Via Veneto, near Piazza Barberini, the crypts opened to the public in 1851, but it wasn’t until the following year that women were also allowed in. There are several memento mori-styled churches in Europe that make use of skeletal remains, but despite the Church’s stance that it is to help one reflect on mortality, it is still pretty macabre.

If the Goonies taught us anything, it is that every kid-at-heart wants to find a secret cave! Smoo Cave has been properly found, but it’s still amazing, and a great place for a unique adventure. Located in Durness in Sutherland, Scotland, the cave was formed ages ago by both the relentless sea, and freshwater dissolving the carbonate dolostones. Appropriately, the name “Smoo” is thought to be derived from the Norse 'smjugg' or 'smuga' meaning ‘hiding place’, and use of the cave is theorized to date back to the Mesolithic Age, with Norse, Neolithic, and Iron Age artifacts having been found in the site.

Although a salt mine might not be the first thing you think of when you think of interesting outings, Salina Turda in Cluj County, Romania has been listed on Business Insider’s ten “Coolest Underground Places In The World” and “25 Unbelievable Travel Destinations You Never Knew Existed.” In it, there are several rooms and mines to visit, including the Crivac room, Iosif mine, and the Terezia mine, the latter of which features an underground lake. A popular destination for halotherapy, the mines have welcomed roughly 2 million tourists since opening in 1992.

A peninsula of solid marble is impressive enough, but caves cut into a solid marble peninsula? That's a sight to behold. Located near General Carrera Lake on the Chilean-Argentine border, the Cuevas de Mármol are only accessible by boat - if the weather conditions allow. A local tour company and ferries from Chile Chico, and the bright colors of the cave, change depending on the time of year and the level of the water, meaning no two experiences are quite the same. Carved out of the marble after over 6000 years of tide and waves, this is one of mother nature’s finest wonders.

This isn't your run of the mill run down old church. Located at the original site of the village of San Juan Parangaricutiro, the church was destroyed by lava when the Parícutin volcano formed in 1943. The tops of the church still protrude from the old lava and ash bed to this day. To access the ruins, you must first travel to the village of Angahuan. From there, guides and horses can be hired to either hike the volcano, visit the ruins, or both. The trip to both sites will take 6-7 hours, so it can be done in a single, glorious day.

While they are becoming more and more in vogue, they are no less fascinating. Beneath the streets of Paris lie the catacombs, which are at once disturbing and breathtaking. Over six million skeletal remains are relocated here, in a section of the old stone mines as a solution to the overcrowded cemeteries Paris faced in the mid-to-late 18th century. Forgotten for a time, the ossuaries opened again in the early 19th century and were made accessible to the public in 1874. If you don’t mind walking among six million of the dead, it is an unforgettable experience waiting to be had.

This small island is located off the coast of the town of Marazion in Cornwall, England. However, because of the tide, it is not always as detached as it may seem. When the water recedes, an ancient causeway opens up and when it appears, it is safe to walk across and visit the island! On the island, you can see the old monastic buildings, the gardens, and the castle – which was a private residence for centuries, and in the care of the St Aubyn family - and now their descendants, St Levan - since the mid-1600s.