I have been going to The Celtic ever since it first opened around 8-9 years ago. It may not be fully ""authentic Irish"", but it is certainly more so than ""Faux-do"" (Fado) near Coors Field. They have a great selection of beers, the ambience is very casual, and (if you happen to smoke), it's just about the only game in town (unless you want to fork over wads of cash to watch strippers at The Diamond Cabaret, or hang out at the rather stuffy Churchill Bar at the Brown Palace). There is also (usually) a live band playing on Saturday nights. \r
If you'd rather not deal with the smoke, you can just wander next door to their sister pub, Delaney's (where they have live music on Fridays).\r
Slainte!
Pros: Ambience (smoke and all), beer selection
Cons: A bit testosterone-heavy some nights
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