Why did Nepal Valley become an important center between South Asia and Central Asia?

The Nepal Valley (now commonly known as the Kathmandu Valley) became a major intellectual and commercial center between South Asia and Central Asia primarily due to the emergence of a powerful, unified kingdom in Tibet between 500 and 700 ce.12

During this period, the opening of Himalayan passes to the north of the valley facilitated extensive cultural, trade, and political relations across the Himalayas. This connectivity transformed the region from a relatively remote area into a vital hub for exchange. These developments were supported by the Licchavi dynasty, whose chronicles and stone inscriptions provide evidence of this era of growth and regional integration.12