The fact, according to geologists, is that the Kathmandu Valley was indeed once a lake, though the valley's waters now drain through the narrow cleft of Chobar Gorge, which was most likely created by a large earthquake.)
Geologists believe that the Kathmandu Valley was a lake at some point in its history.
Later, the island became part of the commercial empires of Pisa, Genoa, and the Spanish, and was annexed in 1718 by the dukes of Savoy.