The so called Old Kalser Way is the easiest way from the southside onto the Großglockner and nowadays the most used.
From the Kalser Glocknerstrasse to the Luckner hut and to the Stüdl hut it only takes 2,5 hours of easy hiking; further crossing the glacier called Ködnitzkees (beware of one big crevasse before the ridge starts), further to the ridge (rope belays) which leads directly to the Erzherzog-Johann-hut, the so called Adlersruhe (another 2,5 hours). From there on it takes you about 1,5 hours to the summit of Grossglockner.
Ausrüstung für Glocknerbesteigungen