Did anyone answer about tunnels under Scott Circle?
https://www.washingtontunnels.com/car-tunnels/
Make sure to check out the other pages with more tunnels under DC. Also note that the infamous James Alefantis may have chosen his name after Pierre L'Enfant because he was very interested in old abandoned tunnels under DC. His restaurants and the pizza museum were all located near such tunnels. He may have been digging new secret entrances into those tunnels. One of the tunnels opens up into a park that is a good place to dispose of bodies.