The world's largest river island, Majuli, is located in the:

Majuli is a large river island in the Brahmaputra river in Assam. It has been recognised by the Guinness World Records (2016) as the largest river island in the world. It is surrounded by the Brahmaputra on the south and by the Subansiri river and the Kherkutia Xuti, a branch of the Brahmaputra, on the north.

Majuli was formed by changes in the course of the Brahmaputra and its tributaries, especially after major floods and an earthquake in the 18th century, notably in 1750. It once covered about 1,250 square kilometres, but because of severe erosion by the river, its area has shrunk to about 350-500 square kilometres today. Erosion and floods are a constant threat to the island.

In 2016, Majuli was declared a separate district, the first island district of India. It is accessible mainly by ferry from Jorhat and Lakhimpur. A road bridge (Majuli Bridge) to connect it with the mainland is under construction.

Majuli is famous as the centre of Neo-Vaishnavite culture in Assam. In the 15th-16th centuries, the saint and reformer Srimanta Sankardev and his disciple Madhavdev established monasteries called "satras" here. Majuli has many satras, such as Auniati, Dakhinpat, Garamur and Kamalabari, which preserve traditions of Sattriya dance (one of India's eight classical dances), music, mask-making and drama ("Bhaona"). The island is also home to the Mising tribe, known for their stilt houses (chang ghar) and handloom weaving. Its pottery is made by hand, without a wheel.

Majuli has been nominated for the UNESCO World Heritage list.

Other notable river islands in India include Umananda, a tiny inhabited river island in the Brahmaputra at Guwahati, known for the Umananda Temple; and Srirangam, an island in the Kaveri river in Tamil Nadu.

Why not the other options?

• ✗The Ganga has islands such as those in the Sundarbans delta, but not Majuli.
• ✗The Godavari forms islands in its delta, near Rajahmundry.
• ✗The Mahanadi forms a delta in Odisha.