The Pajares pass in the north of Spain is one of the most impressive mountain lines of Europe, with more then 60 tunnels, loops and some viaducts. In fact it is more a ramp, with a grade of 2 %, climbing from sea level in Gijon via Oviedo and over the Cantábrica mountain range to the inner spanish highland. The highest point is 1270 meter a.s.l. at the south portal of the 3072 meter long Perruca tunnel below the Pajares pass. The mostly single track line in the iberian broad gauge of 1668 mm (5 ft 5 21⁄32 in) was built between 1864 and 1884 and electrified in 1924 with 3000 V DC. The line on the north side of the pass is difficult accessible and more then the half is in tunnels. A long, narrow windy road goes up to the little stop of Linares-Congostinas, 778 meter a.s.l. Variable gauge Talgo train of the 130 series "Patito" is running as Alvia 4111 service from Castello de la Plana to Gijón through the lonely station.
