It was the first of the National Parks of Spain along with Ordesa y Monte Perdido National Park in the Pyrenees. When it was created 22 July 1918 it covered the western part of today's national park, centered on the Lakes of Covadonga. The Parque Nacional de la Montaña de Covadonga, as it then was called, had an area of 169.25 km². On May 30, 1995 the park was extended to include its current total area of 646.60 km².
On July 9, 2003 UNESCO approved Biosphere Reserve status for the National Park. Picos de Europa is one of several biosphere reserves in the Cantabrian Mountains which are being integrated into a single super-reserve to be known as "Gran Cantábrica"