Afghan Church
Also known as the Church of St. John the Evangelist, this church was built in 1847 and is dedicated to the soldiers who died in the Sind campaign of 1838 and the Afghan War of 1843. There are plenty of memorial plaques and some fine stained glass windows. 
Address: Navy Nagar, Colaba, Mumbai 400005
Phone: 022-22020420

St. Thomas Cathedral
The Anglican St. Thomas Cathedral is located at the centre of the Veer Nariman road and Cowasji Patel Street. It is the oldest English building standing in Mumbai. Its foundation was laid in 1676 during the governorship of Gerald Aungier, but it was not finished until a Christmas day in 1718. A fountain designed by Gilbert Scott stands in the courtyard. Its tower and garden continue to form a significant landmark of the city.
Address: Veer Nariman Rd, Near Akbarallys, Fort, Mumbai- 400050. Phone : 022-22839783

Basilica of Mount Mary
Basilica of Our Lady of the Mount Mary in Bandra, commonly referred to as Mount Mary was built by the Portuguese in 1640. The church is famous for the rituals used to reinforce the power of prayer. The best time to visit the church is during the huge Bandra Fair, held here on 8 September each year.
Address: Mt. Mary's Road, Bandra West, Mumbai- 400050. Phone: 022-26423152

Haji Ali Mosque
Situated at the end of a 500m causeway protruding into the Arabian Sea is the whitewashed Haji Ali Mosque, containing the tomb of a Muslim saint Haji Ali who is believed to have meditated on these very shores. Read more..

Jain Temple
Built of  marble in 1904, the shrine located at Malabar hill is dedicated to Adinath, the first Jain Tirthankara. The walls of the temple are adorned with colourful paintings depicting various incidents in the lives of the 24 Tirthankaras of the Jain Religion. On the first floor is a special shrine dedicated to Parsvanath carved out of black marble and the ceiling shows the different planets as personified in Hindu mythology. 
Address: 41 Ridge Road, Malabar Hill, Walkeshwar, Mumbai-  Phone : 022- 23692727

Mahalakshmi Temple
An important Hindu temple dedicated to the goddess of wealth, Lakshmi.
Address: Bhulabhai Desai Road, Mumbai-400026. Phone : 022-24824732

Walkeshwar Temple (Lord of Sand)

Photo Courtesy : Caryn

Walkeshwar Temple or the Lord of the Sand temple is one of the oldest heritage sites in Mumbai. Situated on Malabar Hill, the original Walkeshhwar Temple was built by the Silaharas around 1050 years ago. According to Ramayana, Rama rested here on his way to rescue Sita in Lanka and constructed a lingam of sand at the site. The original Walkeshwar Temple was destroyed by the Portuguese and the sand lingam is said to have jumped into the sea to avoid desecration.

The temple was rebuilt by Rama Kamath in 1715,  though the current temple dates only 1950's. The shrine is the focus of much religious activity during Diwali, which celebrates Rama's homecoming. The Banganga tank, attached to the temple, is one of the oldest structures in Mumbai.
Address: Banganaga Road, Malabar Hill, Walkeshwar, Mumbai- 400026