I was about to tell you about some really great independent bookstores around Dupont Circle but then I realized you're not looking for that kind of bookstore!

If your friend is right and the bathhouse is in Navy Yard I would strongly recommend that you either 1) not go or 2) take a taxi there and back. Have the number of the taxi with you so that you can call from there to have it pick you up.

There's lots of good bars and stuff around Dupont Circle though. Enjoy your trip!!