Hyderabad is the capital and largest city of the southern Indian state of Andhra Pradesh. Occupying 650 square kilometres (250 sq mi) on the banks of the Musi River, it its India's fourth most populous city and sixth most populous urban agglomeration.
Established in 1591 CE by Muhammad Quli Qutb Shah, fifth sultan of the Qutb Shahi dynasty of Golkonda, Hyderabad remained under the rule of the Qutb Shahi dynasty until 1687, when Mughal emperor Aurangzeb conquered the region and the city became part of the Mughal empire. In 1724, Asif Jah I, a Mughal viceroy, declared his sovereignty and formed the Asif Jahi dynasty, also known as the Nizams of Hyderabad. The Nizams ruled the princely state of Hyderabad in a subsidiary alliance with the British Raj for more than two centuries. The city remained the capital from 1769 to 1948, when the Nizam signed an Instrument of Accession with the Indian Union as a result of Operation Polo. Between 1948 and 1956, Hyderabad city was the capital of the Hyderabad State. In 1956, the States Reorganisation Act merged the Telangana region of Hyderabad State (1948–56) with Andhra State to form the modern state of Andhra Pradesh, with Hyderabad city as its capital.
Historically, Hyderabad was known for its pearl and diamond trading centres. Industrialisation attracted major Indian manufacturing, research and financial institutions, such as Bharat Heavy Electricals Limited, the Defence Research and Development Organisation, the National Geophysical Research Institute, the Centre for Cellular and Molecular Biology and the National Mineral Development Corporation. The formation of an information technology (IT) Special Economic Zone (SEZ) by the state agencies attracted global and Indian companies to set up operations in the city. The emergence of pharmaceutical and biotechnology industries in the 1990s and the formation of Genome Valley earned it the title "India's pharmaceutical capital". The Telugu film industry is based in Hyderabad.
Notable places of interest include Chowmahalla Palace, Charminar and Golkonda fort. Hyderabad has several museums such as Salar Jung Museum, Nizam Museum, and AP State Archaeology Museum as well as home to bazaars such as Laad Bazaar, Madina Circle, Begum Bazaar and Sultan Bazaar, dating from the Qutb Shahi and Nizam era.