Alaska's Portage GlacierWith polar ice caps melting at an alarming rate, now's the time to visit some of the most awe-inspiring natural formations that Earth has to offer -- glaciers. From South America to northern Europe, glaciers rise like ice behemoths, carving out valleys and paving the way for fjords. Here are three of the most breathtaking.

 

 

Perito Moreno Glacier, Argentina

Perito Moreno Glacier in Argentina

Perito Moreno's imposing ice wall is fed from the Andes and is one of Argentina's biggest tourist destinations. Viewing decks afford astonishing views of one of the most visually stunning glaciers in the world.

Grinnell Glacier, Montana

Grinnell Glacier and Mt

Like many of the glaciers in Montana's Glacier National Park, Grinnell continues to recede at a rapid rate because of climate change. According to the U.S. Geological Survey, Grinnell Glacier has shrunk by 40 percent since 1966, and if climate change continues at this pace, Grinnell will be gone by 2030. All the more reason to see this majestic glacier before it disappears forever.

Eyjafjallajökull, Iceland

There's a volcano inside Eyjafjallajokull Glaier

Who says glaciers have to be cold? Eyjafjallajökull sits on top of a volcano! This is the same Icelandic volcano that wreaked havoc on European air travel in 2010. Nevertheless, visions of volcanic activity in a scene of glacial beauty more than make up for Eyjafjallajökull troublesome eruptions, in our opinion.

While these three glaciers are found on opposite corners of the planet, they're all vulnerable to the same melting fate. And if you want to visit these glaciers but don't want to contribute to climate change through air travel, why not go on a bike tour to your glacial paradise.

--Images by iStockphoto/Nikontiger, Zaharov, Bkamprath, OddStefan

Callum Beals is an editorial intern at Sierra. He recently graduated from UC Santa Cruz, where he studied history and literature. He enjoys hiking, camping, and waking up at ungodly hours to watch soccer games.

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