12 mysterious underground paradises so beautiful you'll forget your way back

Deep underground, the magical, wild caves and giant tombs always fascinate tourists.

More than 1,200 years old, Reed Flute Cave in Guilin, China is a very popular tourist destination. This is a natural limestone cave system with countless strangely shaped stalactites combined with the art of lighting, making Reed Flute shimmering and magical like an underground paradise.

The Crystal Cave in Naica, Mexico is one of the most amazing caves in the world. The Crystal contains crystal blocks that were formed 500,000 years ago, the largest block is 100 meters long and weighs 55 tons. Without protection, you can only stay in this cave for 10 minutes.

Catacombs of Paris, Paris, France will make you shiver when you come here because the entrance, pillars, and walls are covered with human bones. The catacombs are hundreds of years old, more than 300km long, 60m deep and are the burial place of more than 6 million people.

Eisriesenwelt Ice Cave, Austria is like an underground paradise that everyone wishes to visit at least once. Eisriesenwelt is a limestone cave formed millions of years ago with a magical, shimmering landscape with thousands of strangely shaped icebergs.

The Salt Cathedral, Zipaquirá is a famous architectural work of art in Colombia. The church is located 200m underground in the tunnels of a salt mine, built by miners around 1932 for daily prayers.

Salina Turda Salt Mine, Transylvania, Romania is one of the oldest salt mines on the planet. Salina Turda is located at a depth of 100m, and has now been renovated into a tourist attraction with a new design space and many entertainment areas.

The Moscow Metro is the first metro system in the Soviet Union with unique architecture reflecting the history of Russia. Currently, it has 197 stations with more than 9.2 million passengers per day.

Iceland's Thrihnukagigur volcano is the only volcano in the world where you can explore inside. First, visitors must crawl through a 1,200m deep, 3.6m diameter tunnel and then explore the magical multi-colored magma plates.

The Puerto Princesa Subterranean River in Palawan, Philippines is a must-see for tourists. Take a boat trip and explore the caves with stalactites, stalagmites and a variety of marine and mountain ecosystems.

The Fairy Hole in Yucatan, Mexico makes visitors feel like they have entered an underground paradise. The landscape here is wild with clear blue water, dense trees and fresh air. This was once a place where the ancient Mayans worshiped the gods.

The giant sewer system located deep under Saitama city, a suburb of Tokyo, in addition to its drainage function, is also a quite attractive tourist destination. The project consists of 5 concrete tanks 65m high, 32m in diameter and connected by 6.4km long tunnels.

The Basilica of Istanbul, Türkiye is like an underground palace. In the 6th century, the Basilica was used as a water reservoir for the city. Inside the basilica is an impressive upside-down statue of the snake-haired goddess Medusa.

According to Dan Viet