Every Amtrak fan dreams of spending a night on a long-distance train, observing the scenic landscapes rolling outside the window, chatting with other passengers, and enjoying this unique adventure.

Traveling long distances by train can take a long time, but one major railroad company invites passengers to do it in style at a shocking premium.

I upgraded my coach seat to a private roomette on Amtrak's Lake Shore Limited for an extra $110. The 23-square-foot space had two seats, an in-room toilet, a foldable sink, and a tray table. The ...