The Picu Urriellu also known as Naranjo De Bulnes. It is a limestone peak from Paleozoic Era, which is located in Macizo Central region of Spain. The name is derived from a Los Urrieles – name which is used to describe Macizo Central area. The Picu Urriellu is part of Picos De Europa National Park and Cabrates region of Spain. Wilhelm Schulz, in year 1855 its first geological map and topographic was published. With an altitude of 2,529-metres it becomes highest peak within Cantabrian Mountain range. It is considered as a best known summits of Spanish Mountaineering, with 550-meters vertical high wall to the west face. To its foot is Vega Urriellu, is a glacial valley. This valley is formed by quaternary period.
There are many way one can reach to the base of the mountain. While, the easiest way is to drive to Sotres. Thousands of climbers visit because of its hardness of a route crossing to get the great experience.