Leisurely first afternoon: ride The Wheel for skyline views and wander the walkable entertainment complex (ICON Park hours typically 11:00am–late; the Wheel often opens earlier—check exact daily times).
Core NASA attraction: see Shuttle Atlantis, Rocket Garden, astronaut encounters, IMAX films and interactive exhibits. Visitor Complex typically opens 9:00am–6:00pm (hours can vary; verify the day you go).
Elevated park built on old rail lines with art, views and a trek to Chelsea Market for snacks and shopping (High Line open ~7am–10pm; Chelsea Market hours vary).
Ferry tours typically run from early morning to late afternoon; book the first departures to avoid crowds and allow time to tour Liberty Island and the Immigration Museum at Ellis Island (plan 3–4 hours).
Visit the outdoor memorial (open daily) and the museum (typical hours ~9:00am–8:00pm; check in advance). The museum is a moving experience documenting 9/11 and its aftermath.
One of the world's great museums—open typically 10:00am–5:30pm (weekend/late hours vary), spend a few hours seeing highlights like the Egyptian collection and European paintings.