In Herndon, VA near dulles airport there is a toll road that extends into DC. However, if you enter the toll road from the airport you get into special divided

In Herndon, VA near dulles airport there is a toll road that extends into DC. However, if you enter the toll road from the airport you get into special divided lanes that are toll-free for traffic to/from the airport. (Or at least there was two decades ago) I got a ticket that way once when I was visiting because I only knew how to get back to my hotel from the airport so I drove to the airport then to the hotel-- and I guess the police watch for people looping through the airport to avoid the tolls. In my case I wasn't aware of the weird toll/no-toll thing-- I was just lost and more concerned with finding my hotel than the posted 'no through traffic' signs. Later, after moving to VA, I noticed google maps was explicitly routing trips from near the airport to other places to take a loop through the airport to minimize toll costs which would have been quite clever if it weren't prohibited.