Sindabung Volcano
You’re going to have to be joined by an experienced guide when visiting the Sunabung volcano in Sumatra, Indonesia. This active volcano has a history of taking the lives of unsuspecting foreign tourists that are just trying to sneak a peek into this vat of bubbling rock. This volcano hasn’t had a full-blown eruption in around 20 years, but the magma beneath burps up hundreds of pounds of volcanic ash and carbon dioxide. Oh, by the way, this volcano’s ash contains microscopic glass particles that will, quite literally, pop your lungs like balloons. You should probably avoid this place, but if you really want to look inside a volcano, don’t do it for too long.