The Cantabrian Mountains (Cordillera Cantábrica) form Asturias’s natural border with the province of León to the south. In the eastern range, the Picos de Europa National Park contains the highest and arguably most spectacular mountains, rising to 2,648 metres (8,688 ft) at the Torrecerredo peak. Other notable features of this predominantly limestone range are the Parque Natural de Redes in the central east, the central Ubiñas south of Oviedo, and the Parque Natural de Somiedo in the west. The Cantabrian mountains offer opportunities for activities such as climbing, walking, skiing and caving, and extend some 200 kilometres (120 mi) in total, as far as Galicia province to the west of Asturias and Cantabria province to the east. Similar opportunities are available for the traveller of Asturias interested in Caldoveiro Peak.

The Asturian coastline is extensive, with hundreds of beaches, coves and natural sea caves. Notable examples include the Playa del Silencio (Beach of Silence) near the fishing village of Cudillero (west of Gijón), as well as the many beaches surrounding the summer resort of Llanes, such as the Barro, Ballota and Torimbia (the latter a predominantly nudist beach). Most of Asturias’s beaches are sandy, clean, and bordered by steep cliffs, on top of which it is not unusual to see grazing livestock.

The key features of Asturian geography are its rugged coastal cliffs and the mountainous interior. The climate of Asturias is heavily marked by the Gulf Stream. Falling within the Cantabrian belt known as Green Spain it has high precipitations all year round. Summers are mild and, on the coast, winters also have relatively benign temperatures, rarely including frost. The cold is especially felt in the mountains, where snow is present from October till May. Both rain and snow are regular weather features of Asturian winters. In coastal or near-coastal areas, daytime high temperatures generally average around 12 °C (54 °F) – 13 °C (55 °F) during winter and 22 °C (72 °F) – 23 °C (73 °F) in summer.