Mendenhall Ice Caves

Once a month here on the Molten Sulfur Blog, I run content taken from our book Archive: Historical People, Places, and Events for RPGs. This post is one of eighty entries in Archive, each more gameable than the last!

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Mendenhall Ice Caves
Caves of Crystal Waters

The Mendenhall Glacier is twelve miles from downtown Juneau, Alaska. Rising global temperatures have carved beautifully fragile caves in it that stretch twelve miles. The caves are only accessible to those willing to kayak to, then ice climb over, the glacier. With global temperatures still rising, the caves are only a temporary destination, as the glacier is retreating increasingly fast. The caves are otherworldly and surreal, but painfully fleeting.

Most of the glacier is surrounded by a lake formed by its own shedding of water, and the kayak trip out to the caves can be dangerous. Afternoon winds create high waves, and the water is around 35 ̊ F, so being overturned can be deadly for the inexperienced. While traveling on the west side of the glacier, you might hear a crack or a sudden roar as a chunk of ice splits from the glacier and tumbles into the water, forming large waves. Also, there are icebergs in the lake, and they can roll at any time. Once at the beach, if you don’t pull your boats up a good 50 feet, waves from nearby calving ice can suck them back into the lake while you’re away.

The entrance to the ice caves is revealed after a few hours’ hike over crevasses and slick ice sheets. This is the most perilous part of the trip. Due to the nature of the caves, they can collapse without warning. Since the entrance is where the ice is thinnest, it is the most dangerous. The inside of the caves is a multicolored tunnel, ranging from light, dirty blue to a bright turquoise to a deep sapphire. Frozen walls, supported by ice pillars, protect from harsh winds outside, but there is still a steady chill radiating from them, as if you just stepped into a crystal freezer. The caverns have shrunk to as little as a third of their original size in one year, but are still incredibly spacious. Some areas require a descent deeper into the caves, forcing you to climb down one of the walls. The surface of the ice is like crystal waves of varying shades of blue, glazed over with a thin veil of meltwater.

Some regions of the caves have floors only of ice, while others have snow-padded stones. Rocks suspended in the ceiling can fall without warning, adding to the threats within the caves. The echo of running water may draw you deeper into the cave, where you’ll find a fast-flowing river running along the rocky floor. The river, made mostly of meltwater, runs the length of the cave and in some areas creates small waterfall steps. Also, as the glacier receded, it exposed the remnants of an ancient forest, frozen for about a thousand years. No full trees have survived, but chilled stumps of varying height jut out of the ground. Only small portions of the forest have been unearthed and explored, while much of it is still encased in its icy prison, awaiting discovery.

Mendenhall Ice Caves in Play

Natural structures like the Mendenhall Ice Caves could make a treacherous shelter in an arctic survival session. The caves would shelter your PCs from the harsh environment, but would also threaten them with occasional tumbling ice chunks and imminent collapse. Or the receding of the glacier could begin revealing more than just an ancient forest. There could be artifacts frozen in the ice, treasure, or even the slumbering body of something meant to be imprisoned forever. Perhaps during the party’s exploration, a calving glacier sinks their boats and they must find a different way to get back. A combat encounter in such a fragile environment could be interesting too. Excessive force could cause a portion of the cave to collapse. Maybe a cave-in separates the party and they must reunite. Or maybe, during an encounter with a rival party, the entrance to the cave collapses and your PCs must work with their rivals if they are to get out of the caves alive.

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