If you'd asked me, I would have said that there are no fish in the Tidal Basin. It's a big round expanse of brackish water surrounded by monuments and roads in DC, with only a couple of small inlets and outlets. But as I was walking around it during my recent trip, this guy was pulling fish out of there. And they weren't tiny, nasty looking fish, they were nice sized ones. He said that he always had good luck when he fished down there, and he had a bucketful that backed him up. So I guess you can't judge a body of water by it's surroundings.