These two changes created suitable conditions for a rapid construction of further RhB lines, which were intended to open up large parts of the Canton.

In 1895, the Zurich railway pioneer Adolf Guyer-Zeller presented the idea of an Engadine-Orient-Railway, which would have connected Chur, via Thusis and Engadine, and over the Fuorn Pass, with the Vinschgau and Trieste.

It would have passed under the Albula Alps through a 12 km (7.5 mi) long tunnel from the mouth of the Val Tisch to the Inn Valley below Bever.

It was only on 30 June 1898 that the Federal Assembly in Bern finally decided on the construction of the Albula railway line.

Priority was given to the construction of a rail connection to the spa at St Moritz, which at that time was a 14-hour stage coach ride distant from Chur, the terminus of the standard gauge line.

As the steam locomotives of the time were still not particularly powerful, and in order to permit the highest possible speeds, the maximum gradients were restricted to 3.5%, and the minimum curve radius was also generously defined.

Especially problematic was the ascent of the valley between Bergün/Bravuogn and Preda, where, in a distance of 5 km (3.1 mi) as the crow flies, a difference in altitude of over 400 m (1,300 ft) needed to be overcome.

To stay within the maximum gradient parameters, the project supervisor, Friedrich Hennings, devised an intricate alignment, which lengthened the line's formation by 12 km (7.5 mi).

On this part of the line, the construction of the 660 m (2,170 ft) long Rugnux Spiral Tunnels in particular led to problems, because the 4 °C (39 °F) cold mountain water hampered the activities of the workers.

The creation of the tunnel was hampered by unusual problems caused by outflowing water, and these led to the bankruptcy of the building contractor.

Successive extensions to the passing loops at the stations has lengthened them to over 260 m (850 ft), the equivalent of an express train with 13 carriages.

Since the end of the 1990s, the RhB has installed three short double track sections - at Thusis, at Filisur and below Preda - to make the hourly train crossings flow more smoothly.

The next section, between Bergün and Preda, is the most demanding example of rail technology on the Albula line: in order to overcome the height difference of 417 m (1,368 ft) between Bergün and Preda – in only 6.5 km (4.0 mi) as the crow flies – without requiring excessive slopes or radii, the route is extended by 12 km (7.5 mi) by various engineering structures (including three spiral tunnels, two curved tunnels and four valley crossing viaducts).

Soon after departure from Bergün station, where an RhB Crocodile stands as a locomotive monument, the train climbs once again at a rate of 3.5%.

At the hamlet of Naz, near Preda, the line crosses a brief plateau, where, for several years now, there has been a double track section about 1 km (0.62 mi) long.

For the section Thusis - St Moritz, the fast trains require 1 hour 34 minutes, and therefore travel at an average speed of 39 km/h (24 mph).

In the high summer season, there are also special tourist oriented express trains with panorama cars, for which reservations and supplements are required.

The two remaining locos of this class, and the similarly historic Ge 4/6, still operate today at the head of not uncommon special trains.

However, they are in everyday use, and the operational difficulties they face can hardly be compared with those to be found on other railways of this magnitude and gauge, due to the nature of the route, and the density of the traffic.

The most important goods transiting the line are timber, cement and other building materials, mineral oil products and foodstuffs.