In Baltimore, but a good bit from the Harbor is Big Bad Wolf on Harford Road. Excellent beef ribs, pulled pork, and brisket. I find the pork ribs to be a little on the dry side. Various sauces from Carolina Vinegar to a cherry nutmeg are available. The place is mostly take out.
Andy Nelson’s BBQ in the county is also well received.
Both of these places actually smoke their meat. Most BBQ in Baltimore is cooked in an oven or worse yet a microwave.