Saemangeum Seawall

The Saemangeum Seawall is a 33.9-kilometre dyke built straight across the sea between Buan and Gunsan in North Jeolla. It is 1.4 km longer than the Afsluitdijk in the Netherlands (32.5 km), which earned it a Guinness World Record as the longest seawall in the world. Driving along the road on top, you have the Yellow Sea on one side and reclaimed land and a lagoon on the other, with the islands of the Gogunsan archipelago along the way.

History: nineteen years to hold back the sea

The name "Saemangeum" was coined from the Gimje and Mangyeong plains, long known together as the "Geumman" plain: the syllables were swapped to "Mangeum" and "sae" ("new") was added, meaning new land. Construction began in November 1991 and was completed in 2010, with the road opening to the public in April that year. Sources differ on when the Guinness record was registered: April or August 2010. As a huge project that filled in tidal flats, it met strong opposition from environmental groups, and court cases that reached the Supreme Court in 1999 and 2005 halted work for a time.

What to see

• Scale: the dyke is on average 36 m high (54 m at most) and 290 m wide at the base (535 m at most). Most of it lies underwater; the visible part rises 11 m above mean sea level. Some 123 million tonnes of earth and rock went into it, enough to cover 418 km of the Gyeongbu Expressway to a height of 13 m, and the dyke alone cost KRW 2.949 trillion.
• Four sections: Seawall 1 from Byeonsan in Buan to Garyeokdo (4.7 km), Seawall 2 from Garyeokdo to Sinsido (9.9 km), Seawall 3 from Sinsido to Yamido (2.7 km) and Seawall 4 from Yamido to the Gunsan mainland (11.4 km).
• Sinsi Sluice Gate: ten pairs of gates, each 30 m wide and 15 m high and weighing around 480 tonnes, with a lock beside them for ships of up to 400 tonnes.
• Garyeok Sluice Gate: eight gates of the same size, each weighing 484 tonnes. It can release 15,682 tonnes of water per second, three times the discharge of the Soyanggang Dam.
• Sinsido: once the largest of the 63 Gogunsan islands (4.2 km²), now joined to the mainland by the dyke. Hiking trails lead over Wolyeongbong and Daegaksan, and a legend says the Silla scholar Choe Chi-won stayed here.
• Saemangeum Promotion Hall and the 33 Center: the hall covers the history of Korean land reclamation, with a model of Saemangeum and an observation deck. The control centre halfway along the dyke is 33 m tall to echo the seawall's length, and so is the completion monument "Land of Promise", erected in April 2010.

Tripto tips

• Driving: the road over the dyke is National Route 77, known as Saemangeum-ro. There are six rest areas, four viewing decks and 17 car parks, so it is easy to stop along the way.
• Time needed: just driving across takes a little over 30 minutes; with the promotion hall, Sinsido and Yamido, plan half a day.
• Public transport: Gunsan city buses run along the dyke, but routes have changed in the past and services are infrequent. Check the latest timetable or go by car.
• Sunset: Yamido, at the end of Seawall 3, is known for its sunrises and sunsets.
• Nearby: Biung Port at the end of Seawall 4, a tourist fishing harbour built alongside the Saemangeum project, has a big seafood market and raw-fish restaurants, and it is the natural starting point for exploring the Gogunsan islands.