Nhiu Co San is the ninth-highest peak in Vietnam, rising 2,965 meters above sea level. Located in Sang Ma Sao Commune, Bat Xat District, Lao Cai Province, it lies approximately 60 km from the center of Sa Pa town. In the H'Mong language, "Nhiu Co San" translates to "buffalo horn," a name inspired by its curved topography featuring two peaks that jut sharply toward the sky. It is a pristine and challenging destination for "cloud-hunting" treks, attracting a large community of travel enthusiasts. Trekking Guide - October – December: Season for cloud hunting and red maple leaves. - February – April: Rhododendron season. - Travel time: The trek typically spans two days and one night. The most common route involves traveling from Sa Pa to Den Sang Commune, then riding a motorbike for about 10 km along a rough, rocky track to reach Nhiu Co San village before beginning the hike. - Difficulty: This route is rated as moderately difficult (Level 3). The terrain features steep, jagged, and slippery rocky sections; participants require good physical fitness, and hiring a local porter as a guide is recommended for safety.