Tip, get off the red line north of the zoo as it will be a downhill walk to the zoo. Then for your return to Union Station, turn left out of the zoo, and cross the street at some point, to the other metro stop - again, it’s downhill.Later today I’ll be in DC on segment 10 of an 11 segment USA loop. I used the DC Metro for the first from Gaithersburg MD (suburb) to Columbus Circle DC in 1977. At Columbus there was a very long escalator.
But more recently during the pandemic, I used the metro twice and the DC fare structure was too complicated Also a very short trip took three trains.
In Boston one fare fits all and seniors are half price - about $1:40 for the T including subway transfers. The MBTA Commuter Rail is half price tor seniors, or $5.50 for an hour ride from the suburbs.
DC rides from the suburbs are especially cheap off-peak and seniors. I expect DC and Mass subsidize transit to keep cars out of the city.
So for today it’s a trip to the zoo then dinner and music at the Dubliner..ha ha .
... if my legs hold up.