Remember visiting a preservation group in the early 80's. I never understood how low height buses worked. The bus is lower but the gangways inside are the same as a normal height bus. This group had such a bus Potteries NEH 453, the lady let me on and then I saw all the seats upstairs to one side. A clever design, before the advent of the high capacity dingle -deck buses. The RT and RLH were such classic designs.

No central isle on top deck, I've not seen that before, I must be younger than I thought. 😄

This place is brooklands airfild and racetrack this is the london transport building