I'm not sure where the MGM is. You can get to the Metro station by going to the basement level and going through the underground mall without going outside.
If you are thinking National Harbor, then take Uber, 20 mins away
MGM Grand is in Las Vegas, and Crystal City Marriott is in Washington, D.C. I think one of those points is confused with something else.
Aaron killing me. MGM is in Oxon Hill, MD. Near Tanger outlets
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