I'm in love with Grand Central Station. I especially love the Whisper Gallery.
You stand on diagonal ends of the tunnel. One person faces into the corner and talks (not loudly). The sound travels across the ceiling of the tunnel to the listener. I could play there all day.
The cherry blossoms were starting to grow on the Highline
I have loads and loads of images from my NYC trip, but here are a few of my personal favourites.