The corporeal relics of the Buddha have been enshrined in the second dome of the Global Vipassana Pagoda in 2006. These relics were donated by the Government of Sri Lanka and the Mahabodhi Society of India, Bodh Gaya.
This is as per the instructions of the Buddha which can be seen in the Sutta Pitaka that his corporeal remains were to be placed in a stupa where people could meditate in its presence. (Source: Nibbana Sutta of the Digha Nikaya which is a part of the Sutta Pitaka of the Pali Tipitaka).
After the Mahaparinibbana Sutta of the Buddha, his corporeal relics were distributed into 12 parts amongst the different kingdoms of North India and stupas were built to house them. Emperor Asoka retrieved all these relics, divided them into smaller parts and enshrined them in 84,000 stupas built across India. The Archaeological Survey of India has started excavating these stupas.
The relics kept in the Pagoda were excavated from Bhattiprolu, Guntur district, Andhra Pradesh, South India. A golden Wheel of Dhamma marks the center of the Dome roof. Directly above this, in the second dome, the corporeal relics of Lord Buddha have been enshrined. The upper two windows of the Pagoda mark the entrance to the 2nd dome of the Pagoda.