Towns bombed during the Spanish Civil War that were never rebuilt; an international railway station once teeming with Nazi and Allied double agents, now concealing a state-of-the-art dark matter research laboratory; a former munitions dump hewn out of the mountainside; a winery whose vast tanks form a unique architectural site; and various laboratories that have closed down, their experiments frozen in time ...

Although the remains of the old town of Belchite and Canfranc railway station are popular with urban explorers in Spain, many other historic sites - overlooked even by local people - are on the brink of vanishing into oblivion.

For the last ten years, the cameras of Fran Lens, Paco Quiles and Carlos Sanmillán have criss-crossed the country to record these abandoned locations for posterity. Their work is featured in this photo report infused with history and adrenaline.