The Poster House located on 119 W 23rd Street is a small museum that 0ften has some unique poster exhibitions. It is just a few blocks west of the Flatiron building and Madison Square Park. Nearby is the Leggo store and Eataly( eating place) and many stores.
This months exhibition highlights austrian graphics artist julius klinger. He was a leader in commercial visual designs. I really had no interest in his work but, for free, I enjoyed the visit.
This is one of the places in NYC that you should know exists. However, you should check their web site first to see if the current exhibition is something you would like. . The normal entrance fee is 12 dollars but during the year they have “free days”.
Update November 4, 202 fri 10am-10pm: free first fridays at poster house: poster house museum (flatiron) offers free admission with extended hours on the first friday of every month (reg. $12 general, $8 students/seniors). in addition to current exhibitions, a rotating series of activities, workshops, and performances will be scheduled throughout the day. >>
So, put this one in your Flatiron or Madison Square Park folder.
I just remembered that the Harry Potter store is now open near the flatiron building Read this article here to get needed information.