The Abruzzi Spur is the standard and by far the most frequently climbed route on K2. It is a long, serious high-altitude alpine route with major objective hazards, especially avalanche-prone slopes, rockfall, and the exposed Bottleneck beneath seracs near the upper mountain.
Route Outline
Askole / Baltoro Glacier approach -> K2 Base Camp
Base Camp -> Advanced Base Camp / Camp I
Climb the Abruzzi Spur via the House's Chimney, Black Pyramid, Shoulder, and the Bottleneck
Summit ridge -> summit of K2
Descend the same route to Base Camp