Travels in Geology: To the top of Europe: Jungfrau, Switzerland

by Naomi Lubick
Tuesday, June 12, 2018

The 4,158-meter-tall Jungfrau in the Bernese Alps, part of the western Swiss Alps. Credit: ©Wengen-Muerren-Lauterbrunnental AG,

Intrepid visitors can take at least two paths to the top of Europe: an excruciating and dangerous ascent up the north face of the Eiger to the top of the nearly 4-kilometer-tall peak, or a comfortable (if steep) train ride through that mountain that allows less-athletic visitors to reach the neighboring Jungfrau.

Most travelers choose to visit Jungfrau (pronounced YOONG-frow), perched in the Bernese Alps, part of the western Swiss Alps. The train ride is a several-hour ascent through tunnels carved through the mountains in the late 1800s and early 1900s, and makes for an easy way to climb more than 2,000 meters of elevation. The steep tracks require a “tooth-train” that ratchets its way through the more than 7 kilometers of tunnels. The pleasant ride on plush red velvet seats emerges at 3,475 meters at the top of Jungfraujoch, a saddle between Jungfrau and the nearby Mönch peak, and then makes another stop at 3,580 meters at the Jungfraujoch observatory, the Sphinx.

The Mönch (or Monk, at 4,107 meters) and the Eiger may be more famous climbing destinations, but Jungfrau (at 4,158 meters) is of more interest to scientists from around the world. Researchers (and tourists) have been traveling to Jungfraujoch (“Jungfrau” means “maiden” or “virgin” and “joch” means “yoke”) for nearly a century to mount long-term experiments at the Sphinx observatory and the research station below it, at 3,454 meters.

The site is a breathtaking place to visit — not only for its beauty, but also because of the thin air. Setting up and running experiments take longer than you would think, “by a factor of pi,” the station’s director emeritus Erwin O. Flückiger of the University of Bern, recently joked. “Even thinking takes longer. Everything uses oxygen,” he told some recent visitors, so “you have to think ahead.”

The research station began as a meteorology and astronomy observatory in the early 1900s. It has now morphed into an extreme high-altitude research station, where scientists have examined high-altitude medical conditions in experiments with rodents and humans (with an eye toward space travel), environmental issues such as the deposition of pollutants in high-alpine ecosystems, and how photovoltaic cells function at high altitude in experiments for solar power.

One recent photovoltaic project tested solar panels for an experimental solar-powered plane, famed balloonist Bertrand Piccard’s Solar Impulse project. Research on solar and cosmic rays starting here in the 1950s led to two Nobel prizes. Ginette Roland, a physicist from the University of Liège in Belgium, has been tracking neutrons at the observatory to detect incoming solar rays for 40 years, living at the Sphinx off and on for weeks at a time.

Above: An indoor viewing terrace at the Sphinx observatory. Right: Visitors brave the outdoor viewing platform. Credit: Right: Naomi Lubick; left: ©Switzerland Tourism, Engler

In the past decade, environmental scientists have discovered that the mountain is the perfect place to measure pollutants in the winds that travel across Europe. A team from Empa, the Swiss Federal Laboratories for Materials Testing and Research, first reported in 2006 the detection of increasing levels of specific hydrofluorocarbons meant to replace the CFCs that were banned by the Montreal Protocol in 1989 because of their impacts on the ozone layer. From this high peak, the researchers eventually pinpointed the source of the hydrofluorocarbons — also scheduled for phase-out soon due to their effects on climate — to the Po Valley in Italy.

And for the past 75 years, MeteoSwiss, the national meteorological bureau, has tracked the weather here. The agency’s instruments have measured winds that gust across the glacier that fills the valley above Jungfraujoch traveling at more than 100 kilometers per hour.

The windy conditions make conducting high-altitude experiments risky, and the ice that accumulates at such elevations, in centimeters-thick clumps, makes moving parts on scientific devices difficult to maintain. And when the weather gets really bad, some research projects anchored to the Sphinx’s platform blow away — though scientists generally work hard to make sure their expensive equipment is well-anchored, in part to keep their data intact, but also so their equipment does not harm tourists on the observing platforms nearby.

That blustery, snowy, sleety weather led in part to the tunnels that house the train ride to the top of Jungfraujoch. On the way up, occasional stops allow visitors to peer out of windows mounted in the Eiger’s face to the valleys below and the neighboring mountains. The carved-out observing caves give passengers an up-close view of the rocks, which are mostly granite gneiss, at the center of the mountain.

These rocks are the result of the Alpine orogeny that built the mountain range 40 million to 20 million years ago. The collision between the African and Eurasian tectonic plates led to several cycles of uplift (the mountains still rise about half a millimeter a year) and compression, with metamorphism to boot. Old granites, gneisses and schists, with some amphibolites (remnants of oceanic crust thrust over continental crust), overlay younger carbonate sediments. Later erosion and multiple glaciations shaped the valleys. Mesozoic ocean sediments caught up in the orogeny are exposed in places at the top of Jungfrau.

Although the research station is generally off-limits to tourists, you can get pretty close to the highest heights where scientists mount their equipment by visiting the Sphinx observing platform, which offers views of the surrounding mountains and spectacular panorama of the valleys beyond — but only on a clear day. Sometimes, the observatory seems to be perched on an island above a sea of fog, which can also be a staggering view. Beneath the observatory’s visitors' center, with its gift shops, restaurants and scientific displays of current and past experiments at the Sphinx, you can walk through a tunnel carved into the valley’s glacier, the Aletsch Glacier, with icy layers and a smooth ice floor.

Aletsch is the largest glacier in the Alps at 23 kilometers long, and it moves more than 100 meters a year. It is also now retreating rapidly due to natural causes as well as anthropogenic climate change, according to reports from researchers at ETH-Zürich, the Swiss Federal Institute of Technology in Zürich, losing tens of meters every year for the past few decades. Since the 1870s, the glacier has lost a total of 2,885 meters of ice, according to the Swiss Glacier Monitoring Network.

If you have the time and physical ability (and if the weather allows), take the tunnel trail to get out on the glacier and explore the frozen scenery on a pair of skis or a snowboard. Rental equipment is available at Grindelwald Sports ( from April through September, but you will have to pick it up before your trip to the top of Jungfraujoch. (Stopping in the town of Grindelwald, in the valley beneath Jungfrau, may also give you the opportunity to explore the ski slopes and sledding runs nearby.)

If the high elevation proves problematic during your visit, you don’t have to stay at the top of Europe for long. Have a cup of coffee in one of the several restaurants in the visitors' center, look around from the viewing platform, and then head back to the slopes below. The paths that radiate out from Kleine Scheidegg and other nearby villages provide some enticing skiing in winter and beautiful high montane hikes in summer, accompanied by the ringing of cowbells.

Even a quick trip to this region shows why the area surrounding the North Wall of Eiger-Mönch-Jungfrau was designated as a World Heritage Site in 2001, in part because of its geology, alpine ecosystems and large glacier. But despite its moniker as the top of Europe, Jungfrau and its neighboring peaks are by no means the highest on the continent: That honor goes to nearby Mont Blanc, summiting at 4,810 meters.

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