The central pier for the Chao Praya river is under the Tak Sin bridge. You can take an express boat that stops at fixed/numbered points along the river. But you can also charter a private longboat. We took the last option this time.
The Chao Phraya river seems to be full of fish. And the Thai at the taxi-boat stops exploit this by selling old bread to get them into a feeding frenzy. Jules and Jonas had a go at it!