Port Blair is the largest town and a municipal council in Andaman district in the Andaman Islands and the capital of the Andaman and Nicobar Islands, a union territory of India. It lies on the east coast of South Andaman Island and is the main entry point to the islands.

It is also the headquarters for the Indian district of Andaman, and the local administrative sub-division (tehsil), which is also called Port Blair. It is home to several museums and a major base for the Indian Coast Guard.

The Ross Island Prison Headquarters, 1872 Map of Andaman and Nicobar Islands with an extra detailed area around Port BlairPort Blair is named for Lieutenant Archibald Blair of the British East India Company, who unsuccessfully attempted to establish a colony in 1789. Port Blair was re-established in 1858, as the site for a British penal colony.

This was originally on Viper Island, named after Lieutenant Blair's vessel, The Viper. The convicts, mostly political prisoners, suffered life imprisonment at hard labor under degrading, even cruel conditions. Many were hanged, while others died of disease and starvation.

Between 1864 and 1867 a penal establishment was built with convict labor on the northern side of Ross Island.[1] These structures are now in ruins. A crucial part of the Sherlock Holmes novel "The Sign of Four" takes place in this penal colony, depicted from the point of view of a convict.

As the Indian freedom movement continued to grow in the late Nineteenth Century an enormous Cellular Jail was constructed between 1896 and 1906 to house even more Indian convicts, mostly political prisoners, in solitary confinement. It is also known as "Kala Pani" translated as "Black Waters".

For a time during 1943 and 1944, Port Blair was the headquarters of the Indian National Army government under Subhash Chandra Bose.

Although damaged by the 2004 Indian Ocean earthquake, Port Blair survived sufficiently to act as a base for relief efforts in the islands. Known as the Emerald Islands, today this is a recommended site for tourists, with its lush green forest and the blue of the sea. Trivia
Popular singer Jack Johnson's song "Holes to Heaven" is about a surf trip to Port Blair.

Ships transport passengers and cargo between Port Blair and the mainland cities of Kolkata, Chennai and Vishakhapatnam. Ferries link Port Blair to outlying islands. Vir Savarkar Airport is served by domestic Indian air carriers.