This was a thoroughly interesting and lovely walk. It's not really close to Metro, but you can take the bus or walk a bit, as we did. We went now because the Knickerbocker Theater (1920s) was along this trail, but it could also be done later.
This trail also includes a few extra signs that embassies have put up about their buildings' histories. The Lithuanian Embassy is especially worth stopping at.
Also, since we had time and we ended near the zoo, we went there afterward.