If you like to hike surrounded by the beauty of snow and ice, you’re not alone. Glacier hiking is a popular activity that can put people in touch with an awe-inspiring landscape. However, hiking on or near a glacier poses a few dangers different from hiking in snow- or ice-covered landscape that is not glaciated. Make sure you know the essential anatomy of a glacier and its potential dangers, which include crevasses, seracs, and bergschrunds.

Glacier Basics

A glacier is basically a large mass of ice that rests on land or on the sea next to a landmass. Glaciers may be found in regions that are characterized by frequent snowfall and freezing temperatures, such the Alps, the Polar Regions, high alpine environments, and other places in other northern or southern latitudes, such as Alaska and the tip of South America.

Glaciers move slowly across the land in a stream-like manner; this movement contributes to a glacier’s distinguishing characteristics and its potential dangers.

Crevasses

A crevasse is a facture in the surface of a glacier, usually caused by the glacier’s movement over the land underneath it. Large crevasses can be dangerous for a hiker or skier when they’re wide enough for an unsuspecting person to fall into.

In the winter, snow bridges can form over the top of a crevasse, making it invisible. Therefore, a person could step onto a snow bridge and fall into the crevasse below it. Depending on its depth, a crevasse fall could cause injury or death.

In the summer, crevasses may be more obvious and avoidable, but it’s always prudent to travel on a glacier with a partner or with a guide who knows the terrain well. When hiking on a snow-covered glacier, wear a climbing harness, and remain roped to your partner. All parties in a team who hike across a glacier in this manner need to be equipped with appropriate gear, which will include ice axes and most likely crampons, and each person should be trained in crevasse rescue techniques. Therefore, hiking on a snow-covered glacier requires additional gear, experience, and advanced skills.

Seracs

A serac is like an ice cliff; it’s a block of ice that pushes up from the surface of a glacier where crevasses intersect or where the glacier ends. Seracs can be dangerous because they move as the glacier moves. They tower upwards from the surface of the glacier, and they will eventually tumble down. Seracs can move or crash down to the surface of a glacier without warning, and they can also trigger an avalanche in the process.

Hikers should avoid traveling through an area of a glacier that has an abundance of seracs and take an alternate route, if possible. Hikers should only enter into an area that contains seracs if they’re equipped with the proper gear and skills. Weaving through the terrain puzzle that seracs create on the surface of a glacier will often require ice axes, a climbing rope, and technical climbing gear, in addition to knowledge of climbing, anchoring, and rappelling techniques.

Bergschrunds

A bergschrund is a terrain feature much like a large gap or crack that occurs where a glacier pulls away from the land that surrounds it or where a glacier separates from stagnant ice. In the winter, a bergschrund can fill with snow and can become unstable during the melting season.

In warmer temperatures, a bergschrund’s crack becomes wider; therefore, a bergschrund can pose several dangers to hikers who would like to cross over an area where one exists. The lip of a bergschrund could collapse as a hiker traverses it, and the gap between a bergschrund and the ground below could be deep enough to cause injury or death to a person who falls into one. Hikers who choose to cross a bergschrund need the same gear, experience, and advanced skills they will also need in order to survive encounters with crevasses, seracs, and other potentially dangerous aspects of glaciated terrain.