Although New York City has beaches, it is not that easy to get there for everyone who lives in the city, so having a picnic is a classic thing to do here during the Spring/Summer season.
Where else could you have a picnic looking at Lady Liberty? Only on Governors Island. This island is a true oasis in the city.
There is no way to talk about a picnic in New York without mentioning Central Park. You will find a lot of picnic spots, but I suggest two: Sheep Meadow and Harlem Meadow.
This park is the best translation of refuge, as it is literally in Midtown, in the middle of skyscrapers. Try to coordinate the park's cultural calendar - that includes an open-air cinema, performances, gym classes - with a picnic!
This area has so much space and the presence of bridges with the city's skyline makes this region unique. The tip here is to have a happy hour picnic at the end of the day, taking the opportunity to enjoy the sunset views.