The Aletsch Glacier is a mind-boggling sight and riverside Fiesch on the valley floor is a top place to access it. From the village, ride the cable car up to Fiescheralp, change to the Eggishorn cable car and continue up to Eggishorn (2927m). Nothing can prepare you for what awaits on arrival – the full 23km length of the Aletsch Glacier, plus, in the distance, the the glistening summits of Jungfrau (4158m), Mönch (4107m), Eiger (3970m) and Finsteraarhorn (4274m).
If you're really lucky, to the southwest of the cable-car exit, spy Mont Blanc and the Matterhorn.