Bombay is also where the now famous Dharavi slum is to be found. I hesitated for a long time before arranging a visit there, not being sure whether it was an ethical thing to do or not. In the end, after doing some research on the net, and especially after a recommendation from a female friend, I decided to purchase a tour created by an NGO. I really liked the social aspect they bring to the tour. It is prohibited to take photos there, and the tour is conducted by a guide who actually lives in Dharavi. It's all done very respectfully, and I ended up discovering a city within a city and not the slum we often imagine. Don't be afraid to go there; it's a tour I really do recommend, and it will absolutely rid you of any negative preconceptions you may have about such slums.
For the rest, the city of Bombay is a bustling and lively place. Plan your itinerary according to the time you have available as there are many attractions to see. I particularly liked my visit to the Gateway of India monument, and I loved going to the cinema to watch a Bollywood film in Hindi! I also enjoyed my visit to the Chhatrapati Shivaji Terminus, aka Victoria Station. The building is inscribed as UNESCO World Heritage.