Boulder-based uber-hiker Andrew Skurka has begun his 6.5-month, 4,720-mile journey around Alaska and the Yukon, by skis, foot, and pack raft, almost entirely off-trail, through some of North America’s most rugged wilderness. On Saturday, Skurka landed in Kotzebue, Alaska, north of the Arctic Circle, and yesterday he began skiing southward toward the Iditarod Trail. Forecast high: –15°F. If all goes well, he’ll return to Kotzebue around the end of September, having averaged more than 23 miles per day. Surely one of the most ambitious outdoor adventures ever conceived.