As we roll with a C-Class, our vehicle is directly connected to our home. So if we want to go exploring in a city we’re staying in, we need to pack up shop and drive ourselves and our entire home around to do it. This involves getting down off the levelers, unhooking the sewage and electricity and driving around a beast of a bus through often narrow city streets.
Naturally, public transportation can come in quite handy, as we can let the bus drivers get us around.
APTA has a list of all of the public transit systems in the United States. Quite a handy tool.