Nalanda (IAST: Nālandā, pronounced [naːlən̪d̪aː]) was a renowned Buddhist mahavihara (great monastery) in ancient and medieval Magadha (modern-day Bihar), eastern India. Widely considered to be among the greatest centres of learning in the ancient world, and often referred to as “the world’s first residential university”, it was located near the city of Rajagriha (now Rajgir), roughly 90 kilometres (56 mi) southeast of Pataliputra (now Patna). Operating for almost a thousand years from 427 CE until around 1400 CE, Nalanda played a vital role in promoting the patronage of arts and academics during the 5th and 6th century CE, a period that has since been described as the “Golden Age of India” by scholars.

Nalanda was established by emperor Kumaragupta I of the Gupta Empire around 427 CE, and was supported by numerous Indian and Javanese patrons – both Buddhists and non-Buddhists. Nalanda continued to thrive with the support of the rulers of the Pala Empire (r. 750–1161 CE). After the fall of the Palas, the monks of Nalanda were patronised by the Pithipatis of Bodh Gaya. Nalanda was attacked and burnt by Muhammad Bakhtiyar Khilji (c. 1200), but it managed to remain operational for decades (or possibly even centuries) following the raids.

Over some 750 years, Nalanda’s faculty included some of the most revered scholars of Mahayana Buddhism. The historian William Dalrymple, said of Nalanda that “at its apex, it was the undisputed scholarly centre of the Mahayana Buddhist world”. The faculty and students associated with the monastery included Dharmapala, Nagarjuna, Dharmakirti, Asanga, Vasubandhu, Chandrakirti, Xuanzang, Śīlabhadra and Vajrabodhi. The curriculum of Nalanda included major Buddhist philosophies like Madhyamaka, Yogachara and Sarvastivada, as well as other subjects like the Vedas, grammar, medicine, logic, mathematics, astronomy and alchemy. The mahavihara had a renowned library that was a key source for the Sanskrit texts that were transmitted to East Asia by pilgrims like Xuanzang and Yijing. Many texts composed at Nalanda played an important role in the development of Mahayana and Vajrayana. They include the works of Dharmakirti, the Sanskrit text Bodhisattvacaryāvatāra of Shantideva, and the Mahavairocana Tantra.

The ancient site of Nalanda is a UNESCO World Heritage Site. In 2010, the Government of India passed a resolution to revive the ancient university, and a contemporary institute, Nālandā University, was established at Rajgir. It has been listed as an Institute of National Importance by the Government of India.