Gaya is a city of ancient historical and mythological significance. It is one of the major tourist attractions of Bihar. The city is the second largest city of Bihar, after Patna and is also the headquarters of Gaya district and Magadh Division. Gaya is 100 kilometres south of Patna, the capital city of Bihar. Situated on the banks of the Phalgu River (or Niranjana, as mentioned in Ramayana), it is a place sanctified by the Jain, Hindu, Islam and Buddhist religions. It is surrounded by small rocky hills (Mangla-Gauri, Shringa-Sthan, Ram-Shila and Brahmayoni) by three sides and the river flowing on the fourth (eastern) side. The city has a mix of natural surroundings, age old buildings, green areas and narrow by lanes.

Gaya derives its name from the mythological demon Gayasur (which literally means Gaya the demon). According to Vayu Purana, Gaya was the name of a demon (Asura) whose body was pious after he performed rigid penance and secured blessings from Vishnu. It was said that the body of Gayasura was transformed into the series of rocky hills that make up the landscape of Gaya.

Gaya finds mention in the great epics, Ramayana and Mahabharata. Rama along with Sita and Lakshmana visited Gaya for offering PIND-DAAN to their father Dasharath. In Mahabharata, the place has been identified as Gayapuri. About the origin of the name 'Gaya' as referred to in Vayu Purana is that Gaya was the name of a demon (Asura) whose body was pious after he performed rigid penance and secured blessings from Vishnu. It was said that the Gayasura's body would continue to be known as Gaya Kshetra.

Documented history of Gaya dates back to the enlightenment of Gautam Buddha. About 11 km from Gaya town is Bodh Gaya, the place where Gautam Buddha attained enlightenment. Gautam Buddha was a sage on whose teachings, the religion Buddhism was founded. Since then Gaya has been a place of pilgrimage for people all over the world. Gaya further flourished under the rule of dynasties like the Mauryans who ruled from Pataliputra (modern Patna) and covered the area beyond the boundaries of the Indian subcontinent. During this period, Gaya was a part of the Magadh region.

Gaya experienced the rise and fall of many dynasties in the Magadh Region. From the 6th century BC to the 18th century AD, about 2300 - 2400 years, Gaya has been occupying an important place in the cultural history of the region. It opened up with the Sisunaga dynasty founded by Sisunaga, who exercised power over Patna and Gaya around 600 BC. Bimbisara, fifth in line, who lived and ruled around 519 BC, had projected Gaya to the outer world. Having attained an important place in the history of civilisation, the area experienced the bliss of Gautam Buddha and Bhagwan Mahavir during the reign of Bimbisara. After a short spell of Nanda dynasty, Gaya and the entire Magadha region came under the Mauryan rule with Ashoka (272 BC - 232 BC) embracing Buddhism. He visited Gaya and built the first temple at Bodh Gaya to commemorate Prince Gautama's attainment of supreme enlightenment.

The period of Hindu revivalism commenced with the coming of the Guptas during the 4th and 5th century A.D. Samudragupta of Magadh helped to bring Gaya in limelight. It was the headquarters of Bihar district during the Gupta empire.

Gaya then passed on to the Pala Empire with Gopala as the ruler. It is believed that the present temple of Bodh Gaya was built during the reign of Dharmapala, son of Gopala.

Gaya, in the 12th century, was invaded by Muhammad Bakhtiyar Khilji. But the Hindu rulers defeated his generals later. The place finally passed on to the Britishers after the battle of Buxar in 1764. Gaya, along with other parts of the country, won freedom in 1947.