From a time when all of India was an island
It is one of Mumbai’s best-kept secrets. In the western suburb of Andheri, flanked by residential buildings, stands a 225-ft column of ancient rock that once dwarfed everything for miles.
It is a stump of earth that oozed out of the crust as molten lava over thousands of years, and has stood for millions (66 million years, to be sort of exact).
It formed when India was still a floating island that had broken off from Africa and was making its way to where we are now. “Around the time when she was cruising over where Mauritius and the Reunion islands currently are, which happens to be a hotspot in the earth’s crust, a very large body from space came smack and hit the earth at Chicxulub in Mexico,” says archaeologist and historian Kurush Dalal.
That impact delivered shockwaves across the planet, creating a global winter. On the floating island that was India at the time, it is theorised that the battering of the earth fuelled a series of volcanoes. “Some of the lava flows cooled quickly and some, like Gilbert Hill, which was squeezed out of the earth’s crust, cooled much slower and crystallised into these massive stumps of black basalt,” says Dalal.
The basalt column was originally part of a larger hill that has since been blasted and built over. Recent construction activity nearby has broken chunks of basalt off the column too. Before the city does more damage, visit and gaze up at one of the oldest geological formations in the country.