On one of London’s iconic double decker buses is a good way to keep dry, whilst seeing the city. If you have bought a travel pass for the day it is also basically free.
You can tick ✅ off typical London sights:
Lion 🦁 on side of building and top of red post box.
Red phone box
Red buses
Black taxi
Red Post Box
Fish and chip shop
London rain ☔️ , with unusual green double decker in front.
Pink flamingo on wall
But you also get an idea of how multi cultural London is.