Other forms: funiculars
A funicular is a railway that goes up the side of a mountain. A funicular is pulled by a moving cable and involves complex, counterbalanced movements of the cars.
It's a coincidence that the word fun is in funicular, though riding a funicular would likely be very fun indeed: it's a railway that goes up a mountain. The real origin of the word has to do with ropes, cables, and pulleys and the complex way these devices are used to move things: such processes were called funicular. From there, funicular became the name of a train that used a similar cable-operated system to move.