This enormous (300m-long) human-made tunnel and series of caves head into Langjökull glacier at 1260m above sea level. The glistening, LED-lit tunnel and caves opened in 2015 and contain exhibitions, a cafe and even a small chapel for those who want to tie the knot inside a glacier. Tours leave from Húsafell (shuttle adult/child 2000kr/free) or the glacier edge (tour adult/child 19,500kr/free) in summer if you have a 4WD. Tours also leave from Reykjavík (29,900kr), and there are many combo tours (snowmobiling, helicopter).
A maximum of 80 visitors at a time can travel up the glacier by monster truck, then have about 45 minutes touring the glacier – which will continue to creep down the mountain in the years to come.