Cuerno Principal, Variant to Line of First Ascent. Alexandra Schultheis, Michael Cross, and I traveled to Chilean Patagonia for a week-long stay in Towers of Paine National Park. During our visit we attempted a new rock route on the the highest of the Cuerno group, Cuerno Principal. An unexpected boat ride across Lago Pehoe saved at least a day's approach with pack horses and put us at the base of the peak on the same day we left Puerto Natales. At 4:30 a.m. on New Year’s Day Mike and I left the Rio Frances valley and reached the southwest spur four hours later. The broad arête was set at a pleasant angle. Nine ropelengths of easy fifth class led to a brief rest at a snowpatch below a headwall. Two more fun pitches of laybacking and 5.7 face climbing on immaculate rock landed us at a high notch and the Chilean Route. Our high point was the infamous black rockband. Like the British, who nearly bagged the first ascent in 1968, we were stymied by the devious routefinding on the mountain’s final reaches. The immensity of the upper slopes were complicated by a veritable maze of crests and spires tilted at crazy angles. Having climbed 19 pitches in nine hours along with lots of loose third class, we decided to turn back. After a cold bivy, we arrived in basecamp 31 hours after leaving it.