The O stands for the circular nature of this hike (called 'Shengleng Trail' on the national park website), which begins and ends at Wuling Forest Recreation Area. It's may also describe the shape of your mouth upon seeing some of the best high-mountain scenery in the country. After a hard push on the first day to the ridgeline, you never drop below 3000m for the next four days as you reach the summit of a half-dozen peaks including grassy Chryou Shan (池有山; 3303m), crumbly Pintian Shan (品田山; 3524m), black-faced Sumida Shan(素密達山; 3517m), sublime Snow Mountain North Peak (雪山北峰; 3703m), and Snow Mountain Main Peak (雪山主峰; 3886m) on the last…