I want to know the answer to the following question:
Where did the canal that once terminated in Kathmandu originate?
All the background I'm provided with is that "The mountains from where these rivers originate are in the elevation range of 1,500–3,000 metres (4,900–9,800 ft), and have passes which provide access to and from Kathmandu and its valley.". Is that enough to answer the question?