A sea of 500 tents covered Ham Tin Wan beach in Sai Kung during the Labour Day holiday, as mainland tour groups turned the site into a crowded campsite.
Campers from mainland China joined organised tours for the Golden Week break. They slept in rows of tents and cooked hotpot meals on the sand.
By the next morning the sole public bathroom sink was clogged with food scraps. Some tents remained for the next arrivals.
One guide who gave his surname as Shu said he was working on a tourist visa. Each of his four clients paid 888 yuan for the two-day trip.
Authorities now face the task of managing visitor numbers while protecting the landscapes they promote for ecotourism.