@pratik I wonder if “the loo” comes from replacing WC, (No, not Winston Churchill), with “loo” from Waterloo? (Thinking out loud).
@odd I wondered about that too and my first thought was, is there a dry loo? But there exists Bakerloo too so have to look into the etymology for 'loo'
@pratik I took a packaged tour in Great Britain in the early 2000s. One of the things that amused me was the number of places throughout the UK named after Waterloo