We started at a neighborhood called "Mount Vernon" , where there is a Washington Monument tower, the famous Peabody Museum, and a solid "art" museum with a bunch of ancient Egypt and Greek art.
We then went to Fort McHenry, which had a pretty nice museum, with a moving video, and the fort has been restored (a vast improvement from the rolling field that it used to be).
We finished off with the inner harbor: the National Aquarium, several ships to tour, and a great vibe.
I would've loved to go to Camden Yard, since it's a few blocks off the inner harbor, but Orioles were out of town.