New Jersey.
Here, 2 of the federal campgrounds, one in two, still take walk-ups.
See New Jersey on the mapFirst-come Reservable · every dot is a campground in its place
4 campgrounds
Camp Gateway - Sandy HookReservableSeasonalfrom $301 with a bear box21 hike-in sites21 sites10 ftdrinking watertoilets
Mohican Outdoor CenterMixed16 sites1,190 ft469 ft to Yards Creekdrinking watertoilets
Rivers Bend Group CampgroundReservableSites from $1005 with a bear box5 pull-through sites5 sites400 ft213 ft to Delaware Riverdrinking watertoiletsWorthington State Forest CampgroundFirst-come78 sites330 ft364 ft to Delaware Riverdrinking waterUnits in New Jersey
2 with campgroundsSource: USGS Protected Areas Database of the United States (PAD-US) land units
Source: campground records from RIDB, NPS, USFS EDW and BLM, unified by CAMPANAC, refreshed nightly