HOW TO VISIT GEOPARK VOLCANIC ROCK REGION FROM SAI KUNG

Hong Kong is well-known for her hectic cityscape, but maybe not the fact that she actually comprises over 250 islands. Any fan of boat trips, nature lover, or ocean fanatic shouldn’t miss the amusing experience of island hoppingin Sai Kung. Sai Kung, a peninsula on the eastern side of Hong Kong, is surrounded by numerous spectacular islands. Once you get to Sai Kung, walk towards the pier where you will see a crowd of friendly ship owners eagerly introducing different boat tours to you. Travelers who wanna explore more islands with higher flexibility may hire a private boat. But if you’re looking for a low-budget option, you may choose the most popular route which takes tourists to land on two islands and passes by sightseeing spots full of extraordinary rocks. The hexagonal rock columns, widely exposed in Sai Kung, are Hong Kong’s most iconic and globally rare geoheritage. Sai Kung is characterized by long meandering coastlines and numerous islands. With no natural barriers to offer protection, the east-facing areas meeting the sea fall victim to persistent wind and wave erosion. In this setting, the hexagonal rock columns are typically exposed in their true glory. Jin Island, Fa Shan on High Island, the Ung Kong Group, and the Ninepin Group are core distribution zones of hexagonal rock columns in Hong Kong. The shores are rimmed with precipitous cliffs, and rock columns are well exposed with their distinct hexagonal form. Visitors can see a wide range of coastal erosion landforms and breathtaking vistas. 

About 140 million years ago, an active supervolcano, which spanned the whole Sai Kung region, erupted and collapsed. A huge 18-km-long oval basin emerged, called a caldera. Volcanic activity produced a large amount of molten state volcanic material, which was deposited inside the caldera. Under stable environmental conditions in the semi-enclosed caldera, these substances cooled down, congealed and contracted in a regular pattern. During the cooling process, hexagonal network fractures appeared and extended downwards vertically. Eventually, the volcanic materials were sculpted into millions of hexagonal rock columns. Today, hexagonal columnar rock is widely distributed across the site of the ancient caldera, covering the Ninepins, the Ung Kong Group, Tai Long Wan, High Island (including High Island Reservoir and Fa Shan) and Kau Sai Chau. The hexagonal rock columns in Hong Kong are very different from similar rock formations in other parts of the world in both texture and chemical composition. While hexagonal rock columns are found in many regions around the world, most are composed of high-temperature, highly mobile and low-silica basalt. By contrast, hexagonal rock columns in Hong Kong are low-temperature, less mobile and silica-rich rhyolitic volcanic rock. In theory, this volcanic material very seldom develops into hexagonal columnar rock. The rock also has a complex texture, which displays features of lava and tuff. It is truly a globally rare of Hong Kong’s geoheritage. Hong Kong’s hexagonal columnar rock formations have undergone weathering for more than 100 million years, but columns up to 400 metres thick are preserved to this day. Land and sea distribution is over 100 km2 (including marine regions), and the average column diameter is 1.2m, with the largest specimens measuring 3m. Some islands and sea cliffs have columns up to 100m high. These formations are integrated with other coastal erosion landforms, such as sea caves, sea cliffs and sea arches. Together, they make up globally rare geomorphological landscapes and world-class geo-wonders.

How to get There

The best way to get to the Volcanic Rock Region is by Hiring a ferry at Sai Kung Pier, but it is also common to hire a sightseeing boat with appropriate safety features and insurance. You may also join the Sai Kung Volcanic Rock Region Sea Tour at Volcano Discovery Centre or call (852) 2394 1538 to join a Recommended Geopark Guide tour. Warning: Boat tours are Only suitable for days when the weather is calm and stable. To prevent accidents, please observe from a boat and avoid getting ashore. The routes and sights arranged by the guided tours run by travel agencies may be different. For details, please check with the relevant travel agency.

Popular Island Groups to Visit

Sharp Island

Lying just 2 km from Sai Kung town center, Sharp Island is a narrow island in the Sai Kung Inner Sea. This most accessible Hong Kong Geopark attraction is merely 15 minutes by boat from Sai Kung Pier. The island is about 2,500m in length and about 500m across from east to west. The highest point is 136m above sea level and there is an idyllic beach at each end that boasts crystal water and beautiful scenery. Sharp Island has long been a favourite countryside destination and in recent years its unique geological features have gained attention. The island is home to many different types of rock and a wide range of geosites. Among the latter, a natural tombolo that emerges only at low tide and Hong Kong’s famous “rock stars” the Pineapple Bun Rocks are most stunning. Surrounded by reef islets, Sharp Island is a sylvan sanctuary with beautiful natural shores and beaches. Sharp Island Geo Trail in the western part of the island begins at the pier and ends at an islet called Kiu Tau, passing through a beach and the tombolo along the way. Make a start at the Sharp Island Pier. A few steps to the left is a beach with adequate public facilities, while natural outcrops can be found on the right. These outcrops are mainly volcanic rocks occurring through migmatisation of volcanic ash, lapillus and lava. The conjoining link to the tombolo at the end of the beach is strewn with huge boulders mostly composed of rhyolite and granite (quartz monzonite). Manifesting extraordinary cracks, the granite boulders resemble Hong Kong’s iconic snack ― pineapple bun. Fittingly, these boulders have earned the name Pineapple Bun Rocks. When the tombolo emerges at low tide, visitors can walk across to Kiu Tau and walk up to the highest point for a panoramic view of the tombolo, Sai Kung Inner Sea and Clearwater Bay Peninsula.

You can find quite a few igneous rocks on this small island, including volcanic breccia, tuff and rhyolite. Geologists believed that Sharp Island was part of the High Island Supervolcano and most probably the site of the crater or the crater peripheral area. Rocks on the island evolved from early eruptive products of the volcano approximately 143 million years ago, while the hexagonal rock columns originated from later eruptive products. They were formed two to three million years apart. While not as spectacular as the hexagonal rock columns, rock landforms on Sharp Island add to Sai Kung’s rock diversity and fill the lacuna in the geological history of High Island Supervolcano eruptions. It commands significant scientific value. Rhyolite on Sharp Island tells us the course of the lava flow. This rock is made up of lava with relatively high silicon dioxide content (also known as felsic lava) that cooled down after being extruded upon the ground surface. Both the fresh and weathered planes of the rock manifest wave or zebra lamination. Close observation will reveal small quartz and feldspar crystalloids. Rhyolite was usually formed by lava during the late eruption stage when eruption force weakened and explosive eruption moderated into effusive eruption. Due to high viscosity, slow current and other factors, lava usually congealed and consolidated into rock within a short distance from the crater. Rhyolite emergences on the ground surface are limited in number with restricted distribution. In Hong Kong, lava with distinct flow banding occurs only in a few small areas, such as Sharp Island and Tai Long Wan. The chemical composition of rhyolite is similar to that of granite. Rhyolite is a product of rapid condensational consolidation whereas granite developed slowly underground through condensational crystallisation. For this reason, they are obviously different in texture. The tombolo is the most eye-catching geomorphic attraction on Sharp Island. This natural gravel levee is a deposition of sediments transported by wind and waves. Approximately 200m in length, it emerges and vanishes with the ebb and flow of the tide. To see this levee in its true glory, plan your trip well. If you want to walk across to the tombolo, check the tidal information published by the observatory and visit when the tide is below 1.4m. Keep track of time while sightseeing and make sure you return in time. If the tide has already come in, do not attempt to cross. The Sharp Island Geo Trail runs in front of the tombolo. There is a tidal information panel for easy reference.

Kau Sai Chau

You can get to Kau Sai Chau By Kaito Ferry Service from Sai Kung Town, as thre is a ferry shuttle service between the two towns; the trip takes about 30 minutes, but do note that the ferry service is not always an option if you are traveling in the morning and if you if you must reserve enough time for the return trip. The last ferry between Kai Sai Village and Sai Kung is at 4:00 pm. 

Kau Sai Chau is the biggest island in Sai Kung and home to Hong Kong’s only public golf course. Tucked in the south corner of the island is the picturesque Kau Sai Village. The Hung Shing Temple in the hamlet is a historical building dating back to the distant past, but the exact year of completion has not been confirmed. The only clue is that a restoration project was carried out in the 20th year of the Qing Guangxu period (1894), which suggests a history of at least 150 years. In the Kau Sai Village Story Room in the Kau Sai Village Committee Office, there is a display of traditional fishing tools and common local medicinal herbs. Visitors can also learn about traditional fishing methods, the culture of the fishing community, and the island’s festivities from texts and illustrations. After disembarking at Kau Sai Village Pier, turn right at the end of the pier until you reach a large square. Take the steps at the edge of the square to the Kau Sai Chau Herbal Plant Trail. You can get a herbal plant trail booklet at the Kau Sai Village Story Room beforehand, which will help you identify medicinal herbs along the trail. Kau Sai Chau is the biggest island in Sai Kung and home to Hong Kong’s only public golf course, which came into service in mid-December 1995. Kau Sai Village, at the south end of the island, was once a Hakka settlement. In 1952, the colonial government set up the Port Shelter Firing Range, and most parts of Kau Sai Chau and nearby Jin Island were firing targets. To avoid firing-related accidents and injuries, the Kau Sai Village Hakka residents were relocated to the new Kau Sai San Tsuen in Pak Sha Wan, Sai Kung Peninsula. 

The High Island supervolcano came to existence 140 million years ago, and Kau Sai Chau is a part of this site. The geological setting of the island is similar to that of the East Dam of the High Island Reservoir, the Ung Kong Group and the Ninepin Group. Kau Sai Chau is situated in an inner sea, where wind and wave erosion is relatively mild. There are no sheer sea cliffs, and the rock columns are not typically exposed. However, you can still see the basic form of the hexagonal rock columns in the coastal intertidal zone where they emerge. Because of the unstable formation environment at the periphery of the columnar rock range, the rock columns are irregular in shape and have developed many cracks. The Scallop Rock on the east coast of Kau Sai Village is actually a section of a broken rock column. It is 2m in diameter. The Hung Shing Temple is the most important historical building in Kau Sai Village. It is a shrine for Hung Shing, the patron god of the fishing community. The temple is at least 150 years old. This ornately decorated building won the Outstanding Project Award of the 2000 UNESCO Asia-Pacific Heritage Awards for Culture Heritage Conservation. On the 23rd day of the 2nd lunar month each year, the Kau Sai villagers begin celebrating the Hung Shing Festival.

Jin Island

  Jin Island is located at the south of Kau Sai Chau in Sai Kung. Jin is separated from its partner island Kau Sai Chau by an extremely narrow channel. The southern part of Jin Island was being eroded by waves which led the headland land was separated from the main rock to form a sea stack called “Tiu Chung Rock”. Since the sea stack has a crooked shape that looks like “Goldfish waves the tail”. As the erosion proceeds, there is a 30m high long sea arch developed called “Tiu Chung Arch” which is rated as the most beautiful of its kind in Hong Kong. “Tiu Chung Arch” is shaped as a bell in the temple, it looks like a golden bell when the sunshine lights it up.

Ung Kong Group

Together known as the Ung Kong Group, Wang Chau, Basalt Island, and Bluff Island consist of hexagonal columns, which are well exposed along the coast. The southeast-facing coastlines, attacked by the relentless waves and wind, showcase some spectacular columnar joints and precipitous cliffs. The 30m-high long sea arch at Wang Chau, the 45m-high sea arch at Basalt Island, and the Tiu Chung Arch at Jin Island have entered the list of top four sea arches in Hong Kong. 

Ninepin Island

 The Ninepin group is made up of three larger islands, namely EastNinepinIsland, SouthNinepinIsland, and NorthNinepinIsland, and several small rock islets. Imposing hexagonal columns of NorthNinepin Island is particularly breathtaking. Long-term wind and wave erosion of rocks with joints has resulted in many peculiar abrasion landforms. The hexagonal rock columns here are measured over 2 m in diameter, ranking first in the region. 

High Island Reservoir East Damn

To get to High Island Reservoir East Damn, You can book the East Dam Half-day Tour at the Volcano Discovery Centre. A round-trip itinerary is available. For inquiries, please contact the Volcano Discovery Centre (tel: 2394 1538) High Island Reservoir in Sai Kung East Country Park is famous for its scenic beauty. The famous hiking route on its south bank ― MacLehose Trail Section 1 ― is a favorite countryside destination. During the construction of the reservoir, stone was quarried from the cliffs around the East Dam. The excavation work revealed globally rare rhyolitic volcanic hexagonal rock columns and the site became the best spot to see this geo-wonder at close range. The East Dam of High Island Reservoir has so much to offer: magnificent uplands, reservoirs, seascapes, various geological structures, and wave-cut landforms. It is one of the most popular geopark attractions. High Island Geo Trail along the East Dam is an ideal circuit to see hexagonal rock columns at close range. This easy route is generally level with adequate countryside facilities. There are interpretation panels along the way to provide information on various landforms created by natural phenomena. It is a trail for hikers of all ages and interests. 

After WWII, Hong Kong saw sharp population growth that coincided with industrial and commercial development. There was an increasing demand for fresh water. The colonial government signed an agreement with Mainland China in 1964 to import Dongjiang water from the following year. This extra supply was nonetheless not sufficient to meet the huge demand and water rationing had to be imposed from time to time. In the worst periods, water was supplied once every four days. In 1968, the colonial government launched a reservoir project in Plover Cove, Tai Po. A great enclosure was built to connect the island and the mainland. Seawater inside the dam was drained and mud on the seabed was cleared. The enclosure was then filled with freshwater ― Plover Cove Reservoir. In the years that followed, Hong Kong’s population and economy continued to grow rapidly, so did the demand for fresh water. To address the water issue in the long run by increasing fresh water supply, another large reservoir was planned for Kwun Mun Channel in Sai Kung in 1969. The project employed the same engineering approach as Plover Cover Reservoir. High Island was connected with the Sai Kung peninsula by a dam to build a reservoir with the biggest water storage capacity in Hong Kong. Construction kicked off in 1971 and the reservoir came into service in 1978. After Plover Cove, it was the second reservoir constructed in the middle of the sea. The 1970 project was preceded by reclamation work just off Tin Hau Temple in Sai Kung town center. Land was reclaimed from the sea to provide relocation housing for several Hakka communities in Kwun Mun Channel, including 390 villagers of 90 households from Lan Nai Wan and 105 residents belonging to 14 households from Sha Tsui Village. Fishermen who used to operate in Kwun Mun Channel were relocated to Kwun Mun Fishermen Village and Man Yee Fishermen Estate in Tui Min Hoi, Sai Kung. Lan Nai Wan Village on the north coast of Kwun Mun Channel was a 400-year-old Hakka hamlet where farming and fishing were major livelihoods. The village was so named because villagers always got their feet muddy as they had to walk across a mudflat to get home when they returned from fishing trips. Given that lan nai sounded derogative, the village head renamed it Man Yee Wan Village when he registered for relocation. The original Chinese name of High Island Reservoir was quite similar to that of Plover Cove Reservoir. It was thus renamed after Lan Nai Wan Village to avoid confusion. The reservoir began storing water in 1977. At that point, Hakka communities in the former Kwun Mun Channel were submerged and became underwater homesteads. There are stories behind the name Kwun Mun Channel too. In the dialect spoken by the local fishermen, mun is a narrow strait while shui kin means low tide or shallow water. The stretch of mid-stream water west of the East Dam was very shallow. In fact, cross Kwun Mun hikes were organized in the 1970s. From historical photos of these events, we can see that the water was just knee-deep. It is possible that the name “Kwun Mun” actually evolved from “Kin Mun”.

Yim Tin Tsai

To get to Yim Tin Tsai, Take the kaito ferry service shuttling between Sai Kung Town and Yim Tin Tsai at Sai Kung Pier (right next to the Sai Kung Bus Terminus), which takes about 15 minutes to reach the island. The Ferry Route is The Salt and Light Preservation Centre – Yim Tin Tsai (Reception Counter); Visitors can also take kaito ferry services subject to demand from Sai Kung Pier to Yim Tin Tsai.

Yim Tin Tsai’s main attractions can be found in the village. To get there, walk straight ahead from the pier a little way, and then turn right. There are two major attractions in the village: the Yim Tin Tsai Heritage Exhibition Centre (in Ching Po School) and St. Joseph’s Chapel. The village is fronted by historically significant salt pans, encircled by vast mangals. There is a circular hiking trail on the island, which will take you to a hill-top lookout and the Jade-Girdle Bridge, which connects Yim Tin Tsai with Kau Sai Chau. Yim Tin Tsai, in Inner Port Shelter, is only 15 minutes from Sai Kung town centre by boat. On this scenic island is a 300-year-old Hakka hamlet. More than 200 villagers lived here during the peak years, and it was a Catholic community. As times changed, many left the island for the city or started new lives abroad. By the late 1990s, the village was deserted. Restoration efforts have been made in recent years, and today this rural homestead has been completely revitalized. Presenting itself as a new Hong Kong nature and heritage destination, Yim Tin Tsai is co-organizing an art festival with the Hong Kong Tourism Board, which features several large-scale art installations.

Yim Tin Tsai villagers are descendants of a Hakka family, named Chan, who moved from the Shenzhen area to establish a settlement here some 300 years ago. Their main livelihoods were fishing, salt-making, and farming. They named the settlement Yim Tin Tsz Village. Tsz, a variant of Tsai, means village. It reflects the Chans’ memories of their old homestead. The century-old saltpans in front of the village are an important historical site. In the past, fishing and farming were the major economic drivers of Sai Kung. Before the days of electrical appliances, food was usually preserved with salt. To produce this important daily essential, the villagers dug out saltpans and filled them with seawater. Brine was evaporated in the sun through a series of processes to make salt, which was marketed in Sai Kung. Subsequently, salt farming declined, and in the 1920s, the Yin Tin Tsai saltpans ceased production. In recent years, the saltpans were restored. This revitalization initiative won an Award of Distinction at the UNESCO Asia-Pacific Awards for Cultural Heritage Conservation in 2015. The Hakka people have always recognized the importance of education. Dating back nearly a century, Ching Po School was the village primary school. It ceased operation in 1997 because of poor enrolment, as most of the villagers had left the island for better opportunities in the urban area or overseas.. The school building now houses the Heritage Exhibition Centre, which showcases an array of domestic utensils. These exhibits, sourced from the locals, give visitors a glimpse of the Hakka lifestyle in the past.

WHY TAKE BOAT TOURS IN SAI KUNG?

Boat tours in Sai Kung are a popular way for visitors to explore the area's natural beauty, secluded beaches, and pristine islands.  These boat tours typically depart from Sai Kung Pier and offer various itineraries depending on your interests. The Sai Kung Geopark is renowned for its unique rock formations, sea caves, and volcanic landscapes. Many boat tours take visitors on a scenic cruise around the geopark, allowing them to admire the striking natural features up close. Sai Kung is surrounded by numerous picturesque islands, such as Sharp Island, Kiu Tsui Chau, and Yim Tin Tsai. Boat tours often include stops at these islands, where visitors can relax on sandy beaches, go snorkeling or enjoy water sports. With its breathtaking scenery and diverse attractions, a boat tour in Sai Kung promises an unforgettable adventure for nature lovers and outdoor enthusias