What's a good 3-day itinerary for Mumbai?

Start Day 1 in Colaba. The Gateway of India, completed in 1924, faces the harbour, and the morning light at 8 AM hits the yellow basalt at a low angle worth seeing. Walk across to the Chhatrapati Shivaji Maharaj Vastu Sangrahalaya, open since 1922. The Gandhara sculpture gallery on the ground floor needs 45 minutes on its own. Head north through Kala Ghoda to Trishna for lunch at 1 PM. Their butter-pepper-garlic crab costs about 1,800 rupees ($19) and it is, without qualification, the best crab in the city. After lunch, walk 15 minutes past the Rajabai Clock Tower. Finished in 1878, it stands 85 metres tall on the University of Mumbai campus. Continue to Crawford Market, where fruit sellers stack Alfonso mangoes in towers during season, and the entrance bas-reliefs were designed by Rudyard Kipling's father. End at Marine Drive by 6 PM. The curved seafront runs 3.6 kilometres from Nariman Point to Chowpatty Beach. The warm salt air, the crash of waves on the tetrapods, the orange glow off the Art Deco facades. Over 100 Art Deco apartment buildings line this stretch, the second-largest concentration in the world after Miami Beach.

Day 2 shifts north. Reach Mahalaxmi Dhobi Ghat by 9 AM and watch from the footbridge. The scale is something else. Thousands of concrete wash-pens, the slap of wet cotton against stone, the sharp sting of starch in the humid air. It is a working laundry, not a spectacle, so keep your visit to 20 minutes. Walk 10 minutes to Haji Ali Dargah, the mosque on a causeway that floods at high tide. Check tide times or you might end up wading back. The white marble interior stays cool even at 34°C outside. Lunch at Swati Snacks in Tardeo by noon. Their panki, a thin rice-flour crepe steamed inside banana leaves, costs 240 rupees ($2.50). It is a Gujarati dish you won't find outside Mumbai and Ahmedabad. Taxi north to Bandra after lunch. Walk to Mount Mary Church, founded in 1904, where the Bandra Fair draws over 100,000 visitors each September. Bandstand Promenade runs south from there along the sea wall, with the Bandra-Worli Sea Link in full view. Dinner at Bastian at 8 PM. Budget 3,000 rupees ($32) per person.

Day 3 belongs to Elephanta. The ferry leaves from the Gateway of India at 9 AM and the crossing takes about an hour. Tickets cost 250 rupees ($2.65) return at the MTDC counter. The cave temples date to between the 5th and 8th centuries, and the 6-metre Trimurti Sadashiva carving in Cave 1 might be the finest rock-cut sculpture in India. The air inside the caves hangs thick and humid. About 120 steps climb from the jetty, but a toy train covers the flat stretch for 10 rupees. You'll likely be back in Colaba by 2 PM. Spend the afternoon at Mani Bhavan on Laburnum Road, where Gandhi stayed during his Mumbai visits from 1917 to 1934. The rooftop library is small and quiet. Finish at Chowpatty Beach by 6 PM with bhel puri from a stall for 40 rupees ($0.42). Puffed rice, tamarind chutney, raw onion, and crisp sev on a paper plate.

Worth noting if you visit in June or July. Mumbai is currently in monsoon. The humidity sits above 85%, light drizzle tends to persist through the day, and your clothes will feel damp within 10 minutes of stepping outside. That said, the city functions. Trains run, restaurants stay open, and hotel rates drop 30-40% from December prices. The Mumbai local trains cover most routes for 5-15 rupees, but the Western and Central lines during rush hour, 8:30-10:30 AM and 5:30-8 PM, carry some of the most packed commuters on earth. Ola and Uber both work well outside those windows. The one mistake most first-timers make is trying to fit South Mumbai and Bandra into the same afternoon. The distance is 20 kilometres, but traffic on the Western Express Highway can stretch that to 90 minutes. Cluster your days by geography. Three days, three zones, about 28 kilometres of walking and transit total.