Slide Show

Cathedrals of Ice

Photographs by ERIN BRETHAUER

Introduction by SIOBHAN BOHNACKER

In this week’s Journeys Issue, Burkhard Bilger writes about the perils of deep-cave diving and describes an expedition into the uncharted depths of the Chevé cave system, in Oaxaca, Mexico. Bilger writes, “Chevé has what cavers call a Hollywood entrance: a gaping maw in the face of a cliff, like King Kong’s lair on Skull Island. A long golden meadow leads up to it, bordered by rows of pines and a stream that murmurs in from the right. It feels ceremonial somehow, like the approach to an altar.”

This past February, thanks to an unusually cold winter, the sea caves along the Apostle Islands National Lakeshore, in northern Wisconsin, were accessible by foot for the first time in five years. Visitors were able to walk two miles over the thick ice of Lake Superior to see the ice formations that run up the coastline. Erin Brethauer, a photographer living in North Carolina, visited the sea caves with her father, who was training for his twenty-fourth American Birkebeiner cross-country ski race.

Describing the trek to the caves, Brethauer told me, “A steady stream of people cut a colorful line on the horizon. More than a hundred and thirty-eight thousand people visited the ice caves this winter, up from twelve thousand seven hundred in 2009. A couple on cross-country skis pulled their children behind them in little covered sleds. One gentleman we met wore giant fur mittens made from wolf hide, the thumbs made from beaver fur. Along another stretch, a pair of friends sat in a small cave drinking pink champagne with their dog.”

The shorelines along the Apostle Islands have been slowly shaped by the movement of the water of Lake Superior, and by its annual freezing and thawing. Sea caves, which resemble honeycombs, are sculpted in the course of centuries by waves breaking onto cliffs. This impact creates what are called reëntrants, or angular cavities that tunnel into cliffs. When reëntrants join behind the cliff face, sea caves result. When water is trapped in the caves and cavities, and freezes, dramatic ice formations occur.

Brethauer said, “We were struck by the size and coloring of the ice along the coastline. Some ice was a pale blue, while other formations were yellow or reddish, depending on the sediment the water collected when it was freezing. And, once you arrived and looked up at these huge ice formations, you felt so small. I loved watching how people interacted with the caves and ice, climbing or taking pictures. They provided such scale and added to your feeling of wonder. And then, stepping inside one of the caves, looking up, and listening to the silence or the ricochet of sound, it felt like being in a cathedral.”