There's a private subway system for senators under Washington
The Retronaut shows how since 1909 our elected representatives have been traveling in style, first with their own private electric monorail. Some people might think that this is a bit over the top for a distance of less than a mile, that the walk might do them good.
It was quite impressive, with two rails zipping down the tunnel.
But wait, the monorail wasn't fast enough for them, and the senators had to mix with staff, so they replaced it all with a three-car private hyperloopy linear induction-drive system where the senators get a private car in the front of the private train.
Lloyd Alter/CC BY 2.0
No doubt a few senators and Members of Congress would prefer the traditional Chinese method for moving royalty from place to place.