The forests of the Ridge are a lung to Delhi. From here, this enormous city, one of the most populous in the world, is invisible, inaudible. The Ridge is uninhabited, almost. For hidden away in a thick jungle of keekar and babul trees are two very different buildings, just 20 metres apart. A satellite ground station next to a ruined hunting lodge, built more than six hundred years ago. The former is bristling with modernity, large dishes, CCTV and high-security defences.