Exploring ice caves in Alaska

Photo: Overlooking snow-filled valley in Alaska.
Looking toward the valley from Mt. Wrangell Alpine. (Forest Service photo by Adam DiPietro.)

Alaska has an endless supply of amazing landscapes, glaciers, spectacular wildlife, and world class fishing. It also contains some of the most rugged and remote landscapes in the United States. As it so happens, I am lucky enough to live in Alaska, specifically the southeastern town of Juneau.  

I have been living in Juneau for a little over a year now and in that time managed to acquire a great group of adventurous friends — via a Facebook group, on the trail, at beer tastings and even one after a debate about superior oil filter brands at an auto parts store. Each one brings their own expertise and wealth of knowledge, all of which is very much needed in southeast Alaska.

Things here can be beautiful, but what you don’t know can be deadly. The gear you use and the wildlife you can expect to encounter differ vastly from that of the lower 48. As a former resident of Oregon, I remember just grabbing some water, some bug spray and a guide book, and that was all you needed for a hike. In Alaska, a lot of planning goes into each potential adventure. Where I go there are no trails, route descriptions, cell towers or guide books.

The first step involves a few hours spent looking over Forest Service topographical maps. I then create a route and upload it to my GPS. It’s usually a crude guess of where I should go based on the topo maps and grainy satellite imagery. Next, I try to figure out what gear is needed for the adventure. Do we plan on encountering a cliff? A wall of ice? Crossing a river? Each adventure requires its own special equipment. Depending on the sport of the day, some of the most common pieces of gear I have with me are a SPOT device for emergencies, GPS, bear spray, ice axe, crampons, 60 meters of static rope, a helmet, a climbing harness and ascenders.

A photo of a A hiker stops inside the Mendenhall Glacier Caves, Tongass National Forest ()
A hiker stops inside the Mendenhall Glacier Caves, Tongass National Forest (Forest Service photo by Adam Dipietro)

With all that in mind, the picture in the ice cave (left) required a lot of planning and specialized safety equipment. A large cave system exists at the bottom of a 70-foot moulin on the Mendenhall Glacier. A moulin is a vertical shaft in the ice formed when surface water finds a crack and works its way deep into the glacier. Over time, this crack is expanded and eventually becomes large enough to climb into.

Four of us would venture onto the ice to descend into the moulin. In pack rafts, we paddled across Mendenhall Lake. Upon arriving at the face of the glacier we donned our climbing harnesses, helmets and crampons and grabbed our ice axes. A half-mile walk on the glacier took us to the moulin. I rigged up three 22-centimeter ice screws at the lip of the moulin to distribute the weight, attached a 60-meter static caving rope, tossed it into the ice pit and began the descent. As the first one down, I had rope-ascending gear in case an obstruction was encountered or the rope didn’t reach the bottom. Thankfully, we all made it safely to the bottom.

We found a small horizontal passage that had been created by running water. A short, wet crawl led to an expanse of large rooms and a lake under the ice. None of us planned to encounter a lake under the glacier, so I went back and retrieved one of the pack rafts. With a boat, we could paddle across the lake to continue our exploration.

The ice filters out all visible light except for blue. The glacier ice is so dense that it absorbs all the other wavelengths. I was able to capture some of the sights with my humble waterproof point-and-shoot camera.

After exploring all we could, we packed up and worked our way out of the moulin. Climbing up rope with a pack is harder than one would expect. It may only be 70 feet, but it’s a lot more of a workout than a few flights of stairs. After hiking back across the glacier and paddling the lake, we parted ways and I began poring over maps in search of the next adventure.

Photo: row of inflatable pack rafts.
Four pack rafts ready to be used. (Forest Service photo by Adam DiPietro.)
Photo: Adam DiPietro climbing cliff face.
Adam DiPietro ice climbing a hidden waterfall in Silverbow Basin. (Photo courtesy Brian Weed.)

Adam DiPietro is an engineer in Alaska. In his free time, he enjoys taking advantage of all the adventure the state offers.