The Islamic barbarians destroyed it 800 years ago. Not unusual for most societies. The difference here was the sheer scale of the unmdertaking. 10,000 students is huge and properly matched only i think in the modern world.
After all the mass of humanity was illiterate. universities were small.
Revival is present to hear and that is a short step to full vesting as a major institie.
- See more at: http://www.ancient-origins.net/ancient-places-asia/ancient-university-nalanda-and-its-revival-modern-day-001811#sthash.QbIpTxxw.dpuf