Capitol Hill politicians have their own subway system and other underground spaces. The Metro stop is nearby, with easy access. Lobbyists send documents and gifts by bicycle courier. Biden famously commuted in from Delaware by Amtrak.

https://en.wikipedia.org/wiki/United_States_Capitol_subway_s...

https://www.washingtontunnels.com/capitol-hill-map

>Biden made Amtrak trips between Washington and his home in Delaware on most days as a senator when Congress was in session so he could help raise his sons. The Amtrak round trip is actually 220 miles or 354 kilometers, not over 260 miles (418 km) as he described it.

https://apnews.com/article/ap-fact-check-biden-amtrak-e79af0...