In Rick Riordan’s Percy Jackson and the Olympians series, Camp Half-Blood is located on Long Island.
The camp is a training ground and refuge for demigod children, including Percy Jackson. Its magical borders hide it from ordinary humans, while its location connects the ancient Greek world to the modern northeastern United States. Percy first reaches the camp after discovering that Greek myths and gods are real.
Camp Half-Blood is specifically associated with the north shore of Long Island, rather than Manhattan, where several important events in the series also occur. The camp’s cabins are organized by divine parent, and its activities include sword training, archery, and capture the flag.
The location helps explain the series’ modern-mythological premise: Olympus is later placed above the Empire State Building, while the demigod camp remains outside New York City in Long Island’s countryside.