Hard Times in Rockville. 2 minutes off 270 on Nelson Street.
But here's my question -- how do you intend to route the buses to Nats Park from Maryland? As I understand, the GW Parkway is off-limits. Outerloop to 66 and across? Ouch.
You are correct that GW Parkway is off limits to buses, so the alternate route is 495 to 267 E and then 66 E. The decent news is that it only adds 3 extra miles to the trip. The bad news is that you have to continue on 495 for another exit and go through the bottleneck where 267 meets 66. Is it still worth a shot? We think so.