Eccles began climbing in the Alps in the 1860s and made an early ascent of the Matterhorn on 20 July 1869 from the Breuil side, employing J. A. Carrel and Bich as guides, together with two Chamoniards with whom he would subsequently often climb - the Payot brothers, Alphonse and Michel. Alpine historian C. Douglas Milner called Eccles a climber of exceptional calibre and his guides the Payot brothers as the finest that Chamonix could provide at that time. Eccles had a special interest in the mountains of the Mont Blanc massif - Dumler calls him that assiduous Mont Blanc explorer - and made the first ascent of the Aiguille du Plan in July 1871 with Alphonse and Michel Payot. This party also made the first ascent of the Aiguille de Rochefort in 1873 and the Dôme de Rochefort in 1881, the latter via its north-west face.