Federico Bahamontes was the climbers’ climber. Nicknamed ‘The Eagle of Toledo’ he won the King of the Mountains in the Tour de France on 6 occasions (1954, 1958, 1959, 1962, 1963 and 1964), and won the mountains competition in both the Giro (1956) and the Vuelta (1957 and 1958). This, particularly fine, photo shows his distinctive climbing style - one of his trademarks was to up the legs on his shorts (!?!).
On paper, the peak of his career was his overall victory in the 1959 Tour. But the Tour in the late 50s and early 60s was so political - with, particularly French, cyclists ganging up to ensure the defeat of this or that rider - that I wonder if he actually delighted more in the gladiatorial purity of the mountain stages and less in the Machiavellian machinations of the General Classification.
In derailleur terms, I think that he won the 1959 Tour using a Campagnolo Gran Sport, and I also think that the Faema team that he rode for in 1958 and 1960 was a Campagnolo team.
This is one of two photos that I have of Federico Bahamontes. The other is here.