Po Toi Island has a handful of sites where you can stargaze. The lighthouse is the most ideal – a reasonable distance (1.5km) to hike from the pier with camping gear, and sunset views on the house. There's a flat area to the right of the path ascending to the (functioning) lighthouse where you can camp. Past the lighthouse, stairs lead to wind-whipped and wave-thrashed rocks called Nam Kok Tsui ('South Pointy Mouth'). You're officially at Hong Kong's southern-most tip.
There's a store run by an elderly lady just past the pier where you can buy provisions and water, and eat your fill. There's also a bilingual colour map showing points of interest.
