Is there any way to take a taxi to sightsee ANY DC attraction during the 2 hr layover in Dulles airport on a Sat afternoon (4pm)? Thanks!

probably not since you will need about 30 minutes just to get to DC from Dulles airport each way. Also, the traffic in DC sucks no matter what time you go. Best to head to the bar and drink a few.

Hi Jason, Thanks! What a shame as I would have loved to get a look of the city! Didn't realize DC traffic was horrific. Maybe next time......

Generally speaking, if your layover is less than 4 hours, you're really better to stay in the airport since most flights start boarding 35-40 minutes in advance of the departure time, and with the additional security measures, etc. If you want to get out, at least a 5-hour layover is the safest option.

30 minutes is very optimistic. Dulles isn't that close to the city, it's about 20 miles outside it. You could do that from National Airport, though, because there's a metro stop right there and it's very close anyway.