I found out that the discount Vamoose bus line to New York not only picks up and discharges passengers in downtown Bethesda, 20 minutes from my home, but also takes bikes free. I began to see a way. The clinchers: the $50 round-trip fare and a midtown drop-off only 10 minutes from the Greenway.
"Keep it simple" was my motto. Get to Manhattan, bike to Battery Park. Turn around and bike north to the George Washington Bridge. Return to West 31st Street in time for the 5:30 p.m. bus. Go back to Bethesda.
Although it appears on maps as one long trail, the Greenway really is a series of connecting trails built at different times. It is most crowded in the downtown area; the number of bikers gradually lessens as you go north. But despite the many bikers, I'm able to maintain a 10- to 12-mph pace.