When the Albula line was electrified, the RhB ordered a more powerful locomotive to complement the earlier electric locomotives and to replace the last steam locomotives. So the first six Ge 6/6, later called Ge 6/6I, were delivered by SLM, BBC and Oerlikon in 1921. Nine more followed until 1929. In reference to the larger SBB Ce 6/8II, they were also called “Rhaetian Crocodile”.
They stood on two three-axle bogies which were directly connected to the structures housing the traction motors. Each motor transmitted its power via a crank axle and coupling rods to the axles. Among others, the requirements for these locomotives had included a speed of 30 km/h with trains of 150 tonnes on grades of 4.5 percent.
SBB Historic 
The first locomotive to be retired was the oldest one that had an accident in 1974, after 53 years of service. Nine more were retired in 1984 and 1985 after the introduction of the Ge 6/6II and Ge 4/4II. Three more were retired in 1993, 2000 and 2008, with only 414 and 415 remaining operational for heritage purposes. These are still operational today, with four more being preserved in a non-operational state.