Caves

Off the coast of Maharashtra lies a landscape unlike any other. Colossal cliffs, crashing waves, mysterious sea caves and haunted lighthouses – this is the Vengurla rocks archipelago. Two of these islands are home to the biggest known breeding colonies of the Indian swiftlets. Studying these birds in this harsh terrain is no easy feat. Watch Dr Sirish Manchi and Dhanusha Kawalkar tackle challenges as they study the mysterious Indian swiftlet.

The Meghalaya caves series has been one of our most ambitious projects so far. Over the last few weeks, we've taken you on a journey through one of India's least explored ecosystems. Here's a light-hearted sneak peek of the bumps and bloopers along the way, and an introduction of the motley crew that made it happen.

Studies show that it takes a hundred thousand years for the caves to grow wide enough for humans to enter. But once they do, a whole ecosystem opens up for exploration – underground rivers, shimmering pools, a labyrinth of tunnels and lives that thrive in the absence of light.

Few have descended into the absolute darkness of Krem Umladaw. It is one of India's deepest vertical caves and extremely tricky to navigate. However, a rare creature waits at its base. Join Dhritiman Mukherjee and team on an expedition to document the barely known ecosystem.

Under the green valleys of Meghalaya is a spectacular subterranean world of dark tunnels, vertical shafts, underground rivers and a host of creatures. Join Dhritiman Mukherjee and team on an expedition through some of least explored caves in India.