Once, there was a giantess who lived in the mountains surrounding a lake.
She had a problem with the other giants. She did not look so much like a giant, since she was much smaller. She was discriminated among the giants. She wanted her revenge.
This has to stop.
Being smart, she decided to set a trap outside their caves. Since the other giants were greedy and food focused, she placed some food in the trap and added sleeping draughts to them. and they fell for it.
When they fell asleep, she carried them to the lake and threw their bodies into the water.
Since the giants didn't know how to swim, they drowned and died. Their bodies formed a land mass that covered the entire lake. As for the giantess, she became one of the first few humans to live on the land that came to be known as Kathmandu Valley.