We are in WDC approximately 6X a year! We only stay at Marriotts. Our daughter was in college at George Washington University and is now living there after college. She was just married in Oct.........so we fianlly get to stay with "them" for free!! My very favorite Marriott is the Renaissance Mayflower. It is an historic hotel in a very safe, good area of DC and we have loved the "extras" such as calling for a wake up call the night before (so what if we want a wake up call for 9:00AM) because, with that call it entitles you to coffee, tea, and hot chocolate service outside your door! The metro stop is Farragut North and it is just a block from the hotel. The very best Marriott for ease of getting around is the Marriott Metro Center. It is on top of the metro center station which is where most changing of lines will occur. Again, excellent location and good area for dining, getting around, ect. In regards to the other poster, we have stayed at the Residence Inn in Alexandria, and while it is fine, it is 20 minutes into the city, the trains run further apart such as 13 minute intervals rather than 4 minutes. That doesn't seem like much, but when you are tired and ready to go home it is a hassle to get there 45min later. I much prefer staying in the city. If you need a nap, need to stash a purse, freshen up, it is so convenient to just ride the train a few stops.Have a great time,email me if you need further info. I feel like I know the city so well after spending so much time there. It is a great vacation spot. Every thing is free, there is so much to see, the kids will adore the metro line. Good call on not renting a car. It is not worth the aggrevation. You could rent one for the day (from the hotel) just for the day you want to tour Mt Vernon. (George Washington's home)