Amtrak has somewhat uncommon luggage size requirements ... which must be under 28 x 22 x 14 inches. Carry-ons for airplanes are usually much smaller (22 x 14 x 9 inches), so for Amtrak ...

However, if you're shopping for new carry-on luggage, it's best to opt for something that meets the requirements for most major airlines (22 x 14 x 9 inches or smaller). Qatar Airways allows ...