Baltimore is a few habitable neighborhoods and the waterfront surrounded by absolute slum.
If you ride around in an armored personnel carrier its not so bad. ;)
A friend came from Australia and I took the Amtrack with him to NYC. He was astonished beyond words to see block after block of abandoned housing as the train passed through Baltimore. There was nothing even remotely like that where he was from.
Growing up in Maryland, I've visited Baltimore many times. I have a friend who used to live in a nice neighborhood not too far from the Harbor. That said, I wouldn't want to live there. Never know if I'll get killed by a stray bullet intended for somebody else.