Arriving by train puts you at Union Station - Red Line Metro. There are a couple hotels kind of near Union Station and the Capitol. Hotel Monoco is near Verizon Center and about 8 blocks from Mall (around the National Portrait Gallery I think). Metro stop is Gallery Place, yellow and green line metro stops for sure, can't recall if something else stops there. If you are only staying overnight, you may want to think about what to do with luggage since you probably don't want to drag it with you to Smithsonian museums and most of them seem to check bags these days.
I've stayed at the Capitol Hilton and the Mayflower both were nice but likely expensive.
I would avoid Georgetown as a place to stay since it does not have Metro access and you would likely need a cab or bus from Union Station.
Metro Center is around 12th and H - the business district mostly but there are hotels and restaurants in the area.
Crystal City is along the Yellow and Blue line Metro stops. Either Marriott is nice. There are other hotels in Crystal City, a Sheraton, Hilton, Hampton Inn. To get into downtown from here is really easy by Metro.
DC hotels are expensive, weekends or not.
I've stayed at the Capitol Hilton and the Mayflower both were nice but likely expensive.
I would avoid Georgetown as a place to stay since it does not have Metro access and you would likely need a cab or bus from Union Station.
Metro Center is around 12th and H - the business district mostly but there are hotels and restaurants in the area.
Crystal City is along the Yellow and Blue line Metro stops. Either Marriott is nice. There are other hotels in Crystal City, a Sheraton, Hilton, Hampton Inn. To get into downtown from here is really easy by Metro.
DC hotels are expensive, weekends or not.