It's here! Open House New York released its list of the sites that will be open for its 2015 festival, and predictably, it's a doozy. Many of the greatest hits from recent years are back, including the TWA Flight Center at JFK Airport, the Brooklyn Army Terminal, and the Jefferson Market Library. But there are also more than 100 sites that are new to the event as of this year, including the recently renovated City Hall, Google's headquarters in Chelsea, and the beloved World's Fair New York State Pavilion. So how do you decide what to see? Use our list below as a guide: We've picked 20 of the best new-to-OHNY sites to see this year, some of which require reservations. And check out the full list of places to go on Open House New York's website.