Kosambi was a large city in northern India, the capital of the kingdom of Vaṃsa and the scene of several important events in the life of the Buddha. The city was surrounded by walls nearly 6 kilometres long and faced the Yamunā River on the south side. One of the monasteries built in Kosambi during the Buddha’s time, the Ghositārāma, was identified by archaeologists in 1951 and subsequently excavated. King Aśoka had a great pillar erected in the city and this can still be seen amongst the ruins.
‘Excavations at Kausambi-1949-1950,’ Annual Bibliography of Indian Archaeology, 1969.