Located in Port Shelter, Sai Kung, Sharp Island is connected with a small island called Kiu Tau by a tombolo, which is accessible when the tide is low. Remember to check the tidal information before crossing the tombolo, which is accessible only when the tidal level is lower than 1.4 metres. Situated at the rim of the crater of a volcano with a radius of 20 kilometres that used to sit in Sai Kung around 140 million years ago, Sharp Island is an ideal place for observing igneous rocks, as it is home to many different types of rocks, such as breccia, which is composed of pyroclastic deposits, rhyolite, which is characterised by lava flow lines, and quartz monzonite, which is formed as a result of the cooling down of rocks intruded by lava leaking into the cracks. Another local special is the pineapple bun. This pineapple bun is in fact quartz monzonite, whose cracked outer layer, caused by weathering, resembles the crumbly crust of the iconic Hong Kong food item. It can be easily found by the seaside of Sharp Island. On Kiu Tau, there are sedimentary rocks and a viewing point that looks out on Port Shelter.