I'm thinking of doing a solo trip to New York next spring. I love the city and have been several times before, so done the main tourist sights (Empire State, Ellis Island, Top of the Rock - which I will probably do again as the view is so great - bike ride in Central Park, walked the High Line etc) The 9/11 memorial wasn't open when I last went so I will do that, and see a show on Broadway, but are there any other less obvious sights/visits I shouldn't miss?