In just two years, the Christmas pop-up bar has grown from a quirky curiosity to a full-blown phenomenon. They're everywhere in the city, with nearly a dozen on Clark Street alone. With so many festive places to do your holiday imbibing this year, it makes it nearly impossible to decide which ones are worth visiting in such a short season. We checked out as many of the Wrigleyville pop-ups as possible to give you a rundown on what makes each one special.