Book your stay now for the ultimate gaming experience. I'm not sure what they can do about that now, but hey, I'm just the messenger. Enjoy table games, slots, and more at MGM National Harbor casino. I didn't really notice until people kept trying to squeeze by me as I was winning on the slot machine. If you like to gamble, then this may be a problem for you. Space between slot machines and tables is tight. Airport (IAD), about 25 mi northwest of MGM National Harbor Casino. A second option is Washington Dulles Intl. We probably waited for about 40 minutes to order and receive our tacos and frankly, the National Market area could use more seating. But overall, the whole place was overwhelmingly crowded and I don't think the powers that be accounted for the crowds when building such a massive facility, which brings me to my next point. The closest major airport near MGM National Harbor Casino in Oxon Hill is Ronald Reagan Washington National Airport (DCA). I know it's still new since opening in early December however, the lines in the food court were unruly. Additionally, we tried making a reservation at Tap Sports Bar upon arrival, but we were told seating was on a first-come, first-served basis. You can call to make reservations but still, let's get with the times. You should be able to go online to make a reservation. You can't make restaurant reservations online. However, in addition to the pros, of course there are some cons I can't overlook: CONS 1. My overall feeling is that I loved MGM National Harbor and can't wait to spend more time there.