The Port Royal Cays are a small group of uninhabited islands or cays off Port Royal, Jamaica, located at 17°55′06.36″N 76°49′11.96″W / 17.9184333°N 76.8199889°W / 17.9184333; -76.8199889 and arranged in the shape of an atoll with a diameter between 4 and 5 km, and a total area of 12 km2. The land area is about 0.03 km2. There are eight named cays, including South Cay Rock which is sometimes subsumed with South Cay.
Gun Cay, the northernmost, is only 400 metres from the Jamaican mainland.
The main cay is Lime Cay, on the northeastern rim. It measures 380 metres northwest–southeast, and is up to 80 metres wide, measuring 2 ha in area. About half of the area is wooded, the rest is sand and coral. On the western beach is a wooden hut.
The individual cays, clockwise starting in the north: