Check around here if no one answers. Pretty sure that Hickory does. There is a sign at the park I go to. FWIW, keep in mind that they cannot restrict you from keeping it in your car.
(f) Nothing contained in this section prohibits municipalities or counties from application of their authority under G.S. 153A‑129, 160A‑189, 14‑269, 14‑269.2, 14‑269.3, 14‑269.4, 14‑277.2, 14‑415.11, 14‑415.23, including prohibiting the possession of firearms in public‑owned buildings, on the grounds or parking areas of those buildings, or in public parks or recreation areas, except nothing in this subsection shall prohibit a person from storing a firearm within a motor vehicle while the vehicle is on these grounds or areas. Nothing contained in this section prohibits municipalities or counties from exercising powers provided by law in declared states of emergency under Article 36A of this Chapter.