Motion-sick on the hill train — AC coach toilet air or observation car open door, which wrecks you less?

If you are motion-sick, prioritize a forward-facing window seat in a reserved coach, ginger or your usual tablets beforehand, and light food. Observation cars are scenic and breezy near open doors, but the swaying and crowd shuffle make some people worse. AC coaches can help if you get a clean window and avoid sitting beside the toilet end when the door keeps swinging. If diesel and heat trigger you, AC wins; if stale air triggers you, a non-AC window with actual airflow can feel better. Neither is a clinic — pick the seat type you can leave if you need air, and keep water handy.