Harbor Inn is a dive bar. To some people, that's an insult, but I love dives. Especially the ones with character. And you are bound to get some character when you are the oldest bar in Cleveland.
The beer selection is GREAT for such a old, dive-y place. I'd guess over 30-35 craft beers in bottle. And cheap! The most expensive beer is around the $4 range. I go for Happy Hour after work a lot (thurs-fri afternoons) and Miller Lites are $2 and a large selection of shots are $3.
They will let you bring food in since they do not serve food after lunch. They are also great at accommodating for large parties. If you call and let them know you are coming, they will make arrangements. They also have an upstairs party room for the larger groups.
For entertainment, they have 2 dart boards, bar bowling and a TouchTunes machine. The basics, but staples in a good dive bar. If you are downtown and are looking to grab a drink in a laid back atmosphere and want to see a little living Cleveland history, then jump on into the Harbor Inn.