Urban exploration | The essential guide for photographers One January night, Mark O’Neill braved -20°C temperatures in search of forgotten places hidden within a frigid, silent landscape in Serbia. Above the mountain plateau was a crystal clear sky. He discovered this airbase (pictured above) by chance, and much of it had been destroyed in the Kosovo War, during the 1999 NATO bombing of Yugoslavia. It was cold enough to freeze his beard, but he continued on. “We managed to reach the hardened aircraft shelters before we found the red tape warning us of all the land mines,” Mark says. In the end, he brought home this long exposure of that unforgettable night beneath the stars.