Cheap Flights from Baltimore Washington Intl. Thurgood Marshall Airport

my only gripe, almost everyone had two carry-on bags, there is not enough stowage space in the bins, I was in zone 5 and when i boarded there was no room, i only had one carry-on no checked luggage and had to sit with the my bag under the seat in front reducing my leg room and making it uncomfortable on a 4 hr+ flight. If people board with two bags they should be made to put one of them under the seat in front