In Switzerland, the world’s longest railway tunnel is set to officially ope Monday. It took nearly 20 years to complete the 57-kilometer tunnel.

It has taken 17 years and billions of U.S. dollars investment to rip through the Gotthard Massif, part of the Swiss Alps. The huge project is funded by Switzerland alone.

An old railway tunnel has been in use for the past century. But trains need to swerve among the massif to go downhill after traveling through the old tunnel and hence take a longer time. With the tunnel now officially announced opened, officials say the new tunnel will cut the travel time by 45 minutes.

They are also expecting substantial increase in total transport capacity across the Alps, which is apparently beneficial, not only for people living in the Alps, but also for visitors from everywhere aspiring to tour around the beautiful landscapes there. But before that, travelers have to wait until December 2016, when the new tunnel will be put to commercial services.