Historically known as Rājagṛiha, which means house of the king or royal house, Rajgir is an ancient city, located at a distance of 103 km from Patna, the capital city of Bihar, famous as a holy place for the Buddhists, as well for the Hindus and Jains, attracting huge crowds of tourists and devotees from all over the world. Nestled in a green valley and surrounded by rocky hills, Rajgir finds its name in the Hindu epic Mahabharata, where Bhima of the Pandava clan killed Jarasandha, the powerful monarch of Magadha, after a long fight and split him in two. Although in ancient times it was also known as Vasumati, Brahdrathapura, Kusagrapura and Girivraja, which means an enclosure of hill, the date of origin of the place is unknown till today. However, ceramics dating to about 1000 BC have been found in the city and the 2,500-year-old cyclopean wall, built with massive limestone boulders, roughly filled together with minimal clearance between adjacent stones and no use of mortar, which is the characteristic style of masonry of Mycenaean fortification systems, is also located in the region.

History says, the ancient city of Rājagṛiha was the capital of Bimbisāra of Haryanka dynasty, the first ruling dynasty of Magadha, an empire of ancient India. His son, Ajatashatru was a contemporary of both Mahavira and Gautama Buddha and one of the most important kings of Magadha, who forcefully took over the kingdom of Magadha from his father and imprisoned him. Nevertheless, Rajgir was the capital city of the kings of Magadha until the 5th century BC, when Udayin, also known as Udayabhadra, son of King Ajatashatru, laid the foundation of the city of Pataliputra and shifted his capital from Rājagṛiha to Pataliputra, as a better choice for its central location in the Empire of Magadha.

Rajgir is surrounded by five hills named Ratnagiri, Vipulachal, Vaibhavagiri, Songiri and Udaygiri, among which the Ratnagiri Hills envelop the Griddhakuta or the Vulture's Peak, where Gautama Buddha spent several months meditating. Located on about the top of 1312 feet (400 m) high Ratnagiri Hills in the lush-green valley of Rajgir, the white Vishwa Shanti Stupa, also known as the World Peace Stupa, stands 120 feet (36.57 m) tall with a total diameter of 103 feet (31.39 m), studded with four gold gilded statues of Buddha in the four cardinal directions, showing four important events of his life. Completed in 1969, it is one of the 80 Peace Pagodas built around the world by the neo-Buddhist organisation Nipponzan Myohoj, to spread the message of peace and non-violence. The ropeway that leads to it is another attraction of Rajgir, which was gifted by the Japanese spiritual leader Nichidatsu Fujii, a Japanese Buddhist monk, and founder of the Nipponzan Myohoj order of Buddhism. It is believed that Lord Buddha preached the Lotus Sutra or Saddharma Pundarika Sutra near the place, leading to the later establishment of the Tiantai, Tendai, Cheontae, and Nichiren schools of Buddhism.

Located at the foot of the Vaibhava Hill, around 4 km from Peace Pagoda, Brahma Kund is a sacred water tank, known for its association with Lord Buddha and Lord Mahavira. The hot water of the kund, believed to have healing power, likely due to the presence of sulfur, comes from seven different springs, known as Saptarshi or seven sages that are believed to originate from the Saptaparni Caves at the top of the hill and merge into the tank, accessible by a staircase. While separate bathing places are allocated for men and women, there are also faucets with running water where one can bathe. A flight of stairs above the Brahma Kund leads to Pippala cave, a massive stone structure with small caves on all sides, named after the Pipal tree at the cave's entrance, said to have been occasionally visited by the Buddha for meditation. There is another structure is popularly known as Jarasandh ki Baithak, named after King Jarasandha.

Situated near Rajgir Hot Springs, Venu Vana, which literally stands for Bamboo Forest, is a historical park, containing a small pond known as Karandak tank, which was gifted by the Magadha King Bimbisara to Lord Buddha. Excavations in the forest have uncovered the foundations of a room and the bases of nine brick stupas as well as tablets from the 10th-11th century. There is also a beautiful Japanese temple, situated beside the Venu Vana. Saptaparni Cave, literally Seven-leaves-cave, located on Vaibhavgiri Hill, is an important Buddhist cave in Rajgir, believed to be the place where Lord Buddha spent some time before his death. Apart from that, it is also the place, where the first Buddhist council was held after the Mahaparinirvana of Buddha, when a council of 500 Buddhist monks decided to appoint Buddha's cousin Ananda, and Upali, one of the ten chief disciples of the Buddha to compose and deliver Buddha's teachings for the future generations.

Apart from the above, other places of interest in Rajgir include the ruins of the Bimbisar Jail, Ajatshatru Fort, Cyclopean Wall, Maniyar Math, the Sariputta Stupa, Ghora Katora Lake and the Rajgir Heritage Museum.