This is an excellent choice to stay in Arlington, and it is just a block and a half away from the Rosslyn Metro Station. You will be ignored in the restaurant unless you have a suit and wads of cash.
Hotel Palomar is gone from Rosslyn ... welcome Le Meridien Arlington (of the Starwood Family) with its AmuseRestaurant. Check out the menu and great patioviews of the Potomac and Georgetown.
Park the car yourself for $13/day. Corner room -> view of the Washington Monument. You can walk across the river to Georgetown, and conveniently grab the subway a block away to go anywhere else.
The heater in the room doesn't work properly. The warmest temp it can get to is 72 degrees. So if you are expecting some place warm and cozy in winter days, DONT stay here !
Valet parking is $25/day. 10 minutes ride into DC. Corner room has view of the Washington monument. The suites are not very modern but have large bathrooms. Inconvenient elevators.
The staff were wonderful. Don't know what the fragrance is they pump into the air in the lobby but it gave me headaches. Would not go back except to eat. The restaurant, Amuse, really is exceptional.
If you're a runner, ask for a jogging map at the front desk. They have three runs outlined: 2.75, 5.75 and 7mi. Outstanding trail with great views of the DC monuments.