In the summer of 1911, Tolkien participated in a walking holiday in Switzerland, which have inspired his descriptions of the Misty Mountains and of Rivendell. 

«I am.... delighted that you have made the acquaintance of Switzerland, and of the very part that I once knew best and which had the deepest effect on me. The hobbit's (Bilbo's) journey from Rivendell to the other side of the Misty Mountains, including the glissade down the slithering stones into the pine woods, is based on my adventures in 1911: the annus mirabilis of sunshine in which there was virtually no rain between April and the end of October, except on the eve and morning of George V's coronation. (Adfuit Omen!)» (Letter 306 - to his son, 1967)