Take the ferry from Gateway of India to Elephanta Island to explore ancient rock-cut caves with Hindu and Buddhist sculptures. Last ferry departs around 4:30pm but check timings for evening.
Head out early for Murud-Janjira Fort, the famous sea fort renowned for its impregnable structure and history, about 45 minutes drive from Alibaug. Entry fee applies, open from 9am to 5:30pm.