August, 1786
8/8: Frenchmen Jacques Balmat and Michel Paccard became the first to reach the top of Mont-Blanc (14,421 ft/4,807 m), a mountain in the French Alps. Their ascension is generally considered the start of professional mountaineering.  Mont-Blanc is the highest peak in Western Europe:  http://www.benoit-guyot.com/blanc.html#english

(source: The Learning Kingdom