Sharp Island or Kiu Tsui Chau () is the largest

island An island (or isle) is an isolated piece of habitat that is surrounded by a dramatically different habitat, such as water. Very small islands such as emergent land features on atolls can be called islets, skerries, cays or keys. An island ...

in the Kiu Tsui Country Park located at

Port Shelter Port Shelter, known in Cantonese as Ngau Mei Hoi (), is a harbour south of Sai Kung Peninsula in Hong Kong. The water body connects to Inner Port Shelter (known in Cantonese as Sai Kung Hoi; ), as well as Hebe Haven (), Rocky Harbour () and oth ...

Sai Kung Sai Kung may refer to: * Sai Kung Town, or just Sai Kung, a town and administrative area in the Sai Kung District, Hong Kong * Sai Kung Peninsula, a peninsula in Hong Kong * Sai Kung District, an administrative district in Hong Kong, which does no ...

Hong Kong Hong Kong ( (US) or (UK); , ), officially the Hong Kong Special Administrative Region of the People's Republic of China ( abbr. Hong Kong SAR or HKSAR), is a city and special administrative region of China on the eastern Pearl River Delt ...

. The area is most known for fishing, swimming as well as diving. Sharp Island is under the administration of

Sai Kung District Sai Kung District is one of the 18 districts of Hong Kong, a special administrative region of China. The district comprises the southern half of the Sai Kung Peninsula, the Clear Water Bay Peninsula in the New Territories and a strip of lan ...

Geography

The island has a maximum elevation of 136m and an area of 1 km². The two

beaches A beach is a landform alongside a body of water which consists of loose particles. The particles composing a beach are typically made from rock, such as sand, gravel, shingle, pebbles, etc., or biological sources, such as mollusc shells ...

, Half Moon Bay Beach (, also known as Hap Mun Bay), and

Kiu Tsui Beach Kiu Tsui Beach is a gazetted beach located facing Inner Port Shelter in the western side of Sharp Island, Sai Kung District, Hong Kong. The beach has barbecue pits and is managed by the Leisure and Cultural Services Department of the Hong Kong ...

() are located on the island. Both are managed by the Hong Kong

Leisure and Cultural Services Department The Leisure and Cultural Services Department (LCSD), is a department in the Government of Hong Kong. It reports to the Culture, Sports & Tourism Bureau, headed by the Secretary for Culture, Sports and Tourism. It provides leisure and cultural ...

. When the predicted tides at Ko Lau Wan is lower than or equal to +1.40 meters, visitors are able to visit Kiu Tau (), an inshore islet, on foot. Different kind of volcanic rocks can be found on Sharp Island. The most frequent ones are rocks with a peculiar pattern on the surface. Other rocks have an unusual pineapple-shaped form.

History

Origin of the different kinds or rocks

It is believed that about 140 million years ago a volcano was located in Sai Kung. Sharp Island was on the margin of the

caldera A caldera ( ) is a large cauldron-like hollow that forms shortly after the emptying of a magma chamber in a volcano eruption. When large volumes of magma are erupted over a short time, structural support for the rock above the magma chamber is ...

. This is probably the reason for the widely distributed different volcanic rocks from different geological periods around Sharp Island.

Formation of the tombolo

The sea currents near Sharp Island pushed sand and gravel near the shore. After several years they formed a

tombolo A tombolo is a sandy or shingle isthmus. A tombolo, from the Italian ', meaning 'pillow' or 'cushion', and sometimes translated incorrectly as ''ayre'' (an ayre is a shingle beach of any kind), is a deposition landform by which an island become ...

, a natural bridge made of different sized rocks and sand – connecting Sharp Island and Kiu Tau (). At high tide the tombolo is submerged in water and thus can only be seen when the tide goes out.

Biodiversity

There are over 70% of

stony corals Scleractinia, also called stony corals or hard corals, are marine animals in the phylum Cnidaria that build themselves a hard skeleton. The individual animals are known as polyps and have a cylindrical body crowned by an oral disc in which a mo ...

coverage around the island. An endangered flora Tetrathyrium subcordatum is found on the south of the island.

Conservation

A small portion of Sharp Island is designated as the Sharp Island Special Area (). It covers 649 square metres and was designated in 2011. The area is located west of the pier at Kui Tsui Beach. The geology of the area is characterised by

volcanic rock Volcanic rock (often shortened to volcanics in scientific contexts) is a rock formed from lava erupted from a volcano. In other words, it differs from other igneous rock by being of volcanic origin. Like all rock types, the concept of volcanic r ...

s of the

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of th ...

period.

Transportation

Sharp Island is accessible by ferry from

Sai Kung Town Sai Kung Town () or simply Sai Kung () is a town on the Sai Kung Peninsula, facing Sai Kung Hoi (Inner Port Shelter), part of Sai Kung District in the New Territories, Hong Kong. Sai Kung is the central hub of nearby surrounding villages, and he ...

References

External links

Memories of volcanic lava flows － Sharp Island
{{coord, 22.36071, 114.29523, display=title Sai Kung District Islands of Hong Kong Volcanism of Hong Kong Hong Kong UNESCO Global Geopark Tombolos