On the slopes of Mount Hood, six explorers set off in a line up the Sandy Glacier. Eddy Cartaya pulls ahead of the group, a stony expression on his face. Read more here to find out what happens.Eddy Cartaya is a caver with a strong sense of responsibility who wants to see our local lava caves protected. And he's in a unique position to do that as the Deschutes National Forest's law enforcement and investigations officer. When Cartaya introduced himself to the Oregon High Desert Grotto of the National Speleological Society, the local chapter of the national cave exploration and protection group, a light went on among several grotto members. They had heard rumors about someone taking formations from the Lavacicle Cave. This was not only illegal, but directly opposed to the NSS philosophy: "Leave nothing behind but footprints, and take nothing out but photographs." Read more here.On October 10, 2013 Oregon Field Guide will kick off its 25th season with one of the biggest stories in program history. During a half-hour special, Field Guide will take viewers on a stunning expedition right in Portland's own backyard—Mount Hood. Mountaineers Brent McGregor and Eddy Cartaya invited OPB to join an expedition beneath the Sandy glacier to film and photograph the largest known glacier cave system in the lower 48 states. McGregor and Cartaya were the first to systematically explore the massive cave system in 2011. Since then, they have spent more than 300 hours mapping the more than a mile of caves and tunnels underneath the ice. Watch the video here.It's a well-known fact that the majority of an iceberg lies below the surface -- but just as stealthily hidden are their fascinating qualities. Traveling the seas, teeming with life, and sometimes even making a noise called "bergie seltzer," there's so much more than meets the eye. Camille Seaman gives homage to these icy isles.Glaciers are giant sheets of ice, right? Speaking of ice, hear a photographer share her journey through some of the coldest parts of the planet, and see some incredible pictures of polar ice here.Who is Genevieve von Petzinger? This TED Fellow researches ancient cave art.Do you think there's life on Mars? Check out the caves, advises Penelope Boston.

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