# 4 and 5 are the closest to Metro Stations. If you zoom in on the map on Marriott.com using your mouse's scroll wheel it will show you how close they are to the Metro Stations. # 4 is going to be better from the standpoint of walking around as you can easily walk into Old Town Alexandria where there are plenty of restaurants and sights. It is also a much more desirable location IMO because it has some character whereas # 5 is in the old Eisenhour corridor (used to be light industrial a couple decades ago) which is now amassed with new office buildings and the like (very little character).

Take # 2 and 3 off your list IMO. The New York Avenue corridor is not the most desireable area IMO, and this location is not near a Metro Station. The South Pentagon name is very deceiving as this location is actually about 5 miles SW of the Pentagon right off of I-395 and not near a Metro Station.

#1 is in Crystal city, but the southern end of Crystal City, and while Crystal City is busy during the day, at night it is pretty dead. It is close to a mile from the Crystal City Metro Station.

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