On the mountain by rail? In the mid 18th century, it seemed hopeless. The wheels adhered badly to the rails when it became steep. But then the Swiss engineer Niklaus Riggenbach developed a system enabling trains to climb. He received the patent for his rack system in 1863. He placed a rack between the rails, so that a gear wheel could reach the spaces between the crossbars.
There are several railways in the Jungfrau Region with the Riggenbach system, for example the Wengernalp Railway. It is the world's longest purely cogwheel railway at 19.1 kilometres, and it has connected Grindelwald, Lauterbrunnen and Wengen with Kleine Scheidegg since 1893. For a cogwheel railway train, it is quite fast: The latest rail cars reach 28 km/h on the mountain route. Slightly slower downhill!