There are many types of caves in this world and every cave have their own specialty. You must have seen many caves in your life, but you have not seen the cave as it is in Vietnam. Yes, this is the largest cave in the world, inside which a different world is inhabited. The most important thing is that from inside this cave, such scary sounds come from which people are shaken by hearing them. Hearing such scary voices, people are afraid to go near the cave. 10 thousand years old cave of Iran, people still live here Nine kilometers long, 200 meters wide and 150 meters high, this cave is named Hang Son Dung. Inside this cave, there is everything from trees and plants to the forest, clouds, and rivers. This cave, which was millions of years old, was opened to tourists for the first time in 2013. You will be surprised to know that only 250-300 people are allowed to go here every year. The cave was discovered in 1991 by a local man named 'Ho Khanah', but at that time no one could muster the courage to go inside due to the fierce roar of the water and the darkness in the cave. This village is home for birds for six months every year Internationally, this cave was recognized in the year 2009, when a British Research Association gave a glimpse of this cave to the world for the first time. Later in the year 2010, scientists crossed a 200-meter high wall, also known as the 'Vietnam Wall', and found the way to enter the cave. Every year, tourists go inside this cave before August and return again, because after that the water level of the river inside the cave rises. The per person ticket for going inside the cave is about two lakh rupees. The tourists visiting the cave are given training for the first six months. They are taught to walk at least 10 km and rock climbing six times. Only then they are taken to the cave. This 23-year-old converts three-wheeler auto in home