I would suggest a midafternoon arrival. Approach on the 139 heading east towards the Holland tunnel. Stay in the right lanes. Turn right (south) on Marin Blvd. It is the last street before the toll booths.
Exit will most likely be north on Marin, west on 14th St towards I78.
Be ready for a bumpy ride. Those sites are narrow! I hope you or your neighbors don't have slides.
We stayed there 3 nights during the summer of 2018. As a campground, it is little more than a parking lot with water and electric. The shower facilities were well maintained. But you're not going there for the campground. You are walking distance from the water shuttle into Manhattan and really close to the statue of liberty shuttle. You'll be able to see the statue and world trade center from the campground. Enjoy!
If you look closely, you can see the statue in one of the shots and the world trade center in the other.
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