Trains where all seats face the front, so you have to sit against the direction of travel.

I recently took a ride on a historic restored railroad where they run sightseeing tours on period accurate trains with period engines and coaches from the turn of the century. The trip was an out-and-back, and there is nowhere for the train to turn around before the return journey. Everyone was immensely surprised, then, when the conductor came down the aisle and demonstrated to everyone that the seats in those old coaches are reversible, and you can flip the backrest to the other side so you're facing the right way regardless of which way the train is going. They're otherwise 100% symmetrical.

Apparently this arcane technology of the reversible seat has been lost somewhere in the intervening 100 years, never to be discovered again. (In America, anyhow.)