From The Dhamma Encyclopedia
It consisted of two parts, the old city built amongst hills and the new city located on the plain just beyond the hills. Both were surrounded by huge walls, the remains of which can still be seen today. The Buddha’s two favourite places in the city were the Bamboo Grove and a low rocky hill called the Vulture Peak, just beyond the east gate of the city. Numerous places in Ràjagaha which are mentioned in the Tipitaka have been identified and excavated by archaeologists. Ràjagaha is now called Rajgir and is in the modern north Indian state of Bihar.
Rajagaha in Ancient Literature, Memoirs of the Archaeological Survey of India, 1938.