In the morning, visit the iconic Gateway of India. It is a monumental archway situated on the waterfront in South Mumbai. You can take a ferry to the nearby Elephanta Caves, which are UNESCO World Heritage Sites. In the afternoon, head to the Chhatrapati Shivaji Maharaj Vastu Sangrahalaya, a museum that showcases the art, culture, and history of India. In the evening, explore Marine Drive, also known as the Queen's Necklace, which is a 3.6 km long boulevard overlooking the Arabian Sea.
In the morning, take a ferry from Gateway of India to the Elephanta Caves. The rock-cut temples are dedicated to Lord Shiva and have intricate carvings and sculptures. In the afternoon, visit the Hanging Gardens, which are terraced gardens built on a hill slope. From there, head to the Mahalaxmi Dhobi Ghat, an open-air laundromat that is a unique sight to behold. In the evening, watch a Bollywood movie at the iconic Regal Cinema, which has been operational since 1933.
If you have extra time, you can consider visiting the Sanjay Gandhi National Park, which is home to a variety of flora and fauna. You can also take a heritage walk in the Fort area to learn about the colonial history of Mumbai. For side trips, you can visit the nearby hill stations of Lonavala and Khandala. To maximize your fun, try some street food such as vada pav, pav bhaji, and bhel puri. If you're looking for other suggestions, don't hesitate to ask your hotel concierge or tour guide.