In 1871, Switzerland put a toothed rail between normal train tracks so carriages could climb steep Mount Rigi; 155 years later, the same system still works

Somewhere in Switzerland runs a train track with a third rail down the center, cut with teeth like the rungs of a ladder. Under the train is bolted a matching gear that locks into the teeth, so that the wheels cannot slip even on a steep slope. The first system of this type in Europe was built by Switzerland in 1871 on Mount Rigi. The same rack-and-pinion grip system is still carrying passengers up the mountain today, 155 years later, according to a retrospective published by House of Switzerland, the outreach arm of the country's Federal Department of Foreign Affairs.

Why regular trains couldn’t climb high mountains

A standard train wheel grips the rail by plain friction, just like a shoe grips a sidewalk. This works well on level ground. But when a slope gets much steeper than about 4 percent, the wheels begin to slip, especially in rain or snow. Rigi is 1,797 meters high, and before the 1870s visitors could only reach the top on foot, on horseback, or by carriage. The mountain was already a tourist attraction, but the hike was slow and hard, and it ruled out anyone who wasn't fit enough for a long walk.


An engineer solves the grip problem

The solution was found by a Swiss locomotive builder, Niklaus Riggenbach, who lived in Olten. Riggenbach had patented his rack-and-pinion system in France in 1863. The Historical Dictionary of Switzerland states that in 1867, the engineer Carl Culmann, of ETH Zurich, reviewed and publicly endorsed Riggenbach's design, developed as a flat rack in the shape of a ladder between the two normal rails, lending it the institutional credibility that helped secure the Swiss construction concession. Underneath the locomotive, a toothed wheel engaged the rungs of that ladder, giving the train enough grip to climb without slipping, and enough control to brake safely on the way down. Riggenbach tried the idea on Rigi. Work began on the line from the lakeside town of Vitznau in 1869, and it opened to the public on 21 May 1871, the first such mountain railroad in Europe.

A nervous crowd and then a rush of tourists

Newspaper coverage from opening day described a large crowd of business and political people in attendance. Understandably, some of the passengers were nervous about riding a train up a cliff face on new technology. A correspondent of a Geneva newspaper who crossed the line a few months later said that the trained mountain guides went ahead of the first trains for short distances, watching the track, and that the ride felt safer than an ordinary railroad on level ground. What that opening-day crowd rode, however, was not yet the full route. The 1871 line covered only about 5 kilometers and climbed roughly 1,100 meters, stopping at a station short of the true summit. In 1873, engineers brought the line the rest of the way to the top station, Rigi Kulm. News of the safe and pleasant ride spread quickly, and the Rigi was among the first European mountains to be built around a modern tourist industry.

The first section of track was about 5 kilometers long and climbed about 1,100 meters in elevation, ending at a station just below the summit. In 1873, engineers brought the line the rest of the way to the top station, Rigi Kulm. News of the safe and pleasant ride spread quickly, and the Rigi was among the first European mountains to be built around a modern tourist industry.

The technology spreads across Europe

Riggenbach’s system proved reliable, and other places borrowed it quickly. A second line up Rigi, from the town of Arth on the other side of the mountain, opened in 1875. In 1992, the two rival companies were finally merged into one single operator, Rigi Bahnen. Riggenbach’s own manufacturing company later built similar rack railroads in other parts of Europe, including a line up the Kahlenberg hill near Vienna in 1874. Later, the same basic idea found much higher ground. Construction began in 1898 on the Jungfrau Railroad, which climbs to 3,454 meters, and it was finished in 1912.

Still climbing, 155 years later

Rigi Bahnen, the company that currently operates both lines, keeps a public record of the railway's history. This record shows that the Arth side of the mountain was electrified in 1907, the first electrified standard-gauge rack railroad in the world, and the Vitznau side followed in 1937. So while the original 1871 Vitznau line gives the railway its 155-year figure, the two lines have followed slightly different timelines since then. More recently, it also notes that six new electric railcars from Swiss manufacturer Stadler Rail entered service in 2021 for the 150th anniversary of the Vitznau line, and that the Arth line celebrated its own 150th anniversary in 2025, with four more new railcars on order for delivery by 2030. The trains climb gradients of up to 25 percent in places, and that has not altered since Riggenbach designed the line.

Why an old railroad remains important

It’s easy to assume that anything built in the 1800s must be outdated by now. The Rigi railroad takes a different view. One good mechanical idea, a toothed rail and matching gear, has survived two World Wars, several changes of ownership, and a complete switch from steam to electricity. The teeth on the rail just hold, which is the reason it still takes visitors up the mountain today. For a generation used to gadgets that die in a couple of years, that kind of staying power might be worth noticing.