Bac Sum Pass (Đèo Bắc Sum)

Xin Man district has a complex terrain, located in the upper Chay River mountain range, so it is mainly hills with steep slopes and divided by many streams.

Its name, Hoàng Su Phì or Hoàng Thụ Bì, means “the yellow bark” in the Hmong language. It indicates the woods of weeping cypress, which is a local specialty.

Tu San Canyon (Mèo Vạc district), the deepest canyon in Vietnam. It has a depth of about 800 m, a length of 1.7 km, and cliffs that slope 70° to 90°.