Gilbert Hill

Gilbert Hill is a 200-foot column of black basalt at Andheri in Mumbai, with a sheer vertical face. It formed about 66 million years ago, when molten lava was forced up through cracks in the earth during the eruptions that spread lava over large parts of Maharashtra, Gujarat and Madhya Pradesh. Experts see it as the remnant of a ridge, comparable to Devils Tower in Wyoming; similar columns nearby at Jogeshwari were quarried away.

In 1952 the hill was made a national park, and in 2007, after long lobbying by geologists, the city made it a Grade II heritage structure and banned quarrying around it, though erosion remains a problem. A steep staircase cut into the rock climbs to the top, where the Gaodevi and Durgamata temples stand in a small garden. From the summit there is a wide view over suburban Mumbai.