Nanhai No 1 shifts to a new stage of protection

A project to protect Nanhai No 1, a sunken cargo ship from the Song Dynasty (960-1279), has shifted to a new stage of comprehensive protection, research, utilization, exhibition and academic exchange.

Archaeological excavation over the past few years has followed the principle of overall salvage, on-site protection and display, creating a precedent for underwater archaeology, according to the National Cultural Heritage Administration.

The ancient wooden ship sank while transporting Chinese porcelain. It was salvaged in the South China Sea in 2007 and is currently preserved at the Maritime Silk Road Museum on Hailing Island in Yangjiang, Guangdong province.

Data from the heritage authority shows that more than 180,000 cultural relics have been unearthed from the sunken ship. The relics are of great significance for studying the history of ancient shipbuilding, ceramics, shipping and trading in China and Asia.

According to a plan approved by the heritage authority, the retaining structures around the ship for more than 10 years will be removed in 2024, after completion of the current long-term supporting construction.

"Removal of the caissons will allow the public to get a closer view of the ship from a better perspective," said Wang Damin, deputy director of the archaeological research center of the National Cultural Heritage Administration.

Due to more than 800 years of seawater erosion, and the corrosion and pollution of a large amount of iron condensate, the hull components of the ancient ship are relatively fragile.

"The protection of wooden sunken ships in ocean water is a global challenge. It is like a terminally ill old man and is extremely challenging to protect," said Wang.

The body of the ship is the most valuable of all cultural relics and the most difficult to protect, according to Wang.

In addition to completing a long-term stable supporting structure to meet safety needs, an overall spray system will also be built to clean and desalinate the hull components.

"We will complete the filling, reinforcement and dehydration of the ship hull, which will be completely repaired and restored," said Wang.

Shipborne cultural relics will be classified according to their different materials and protected through cleaning, desalination, restoration and stable preservation, according to Wang.

Porcelain products, gold, silver, copper and iron relics, and copper coins are just some of the 180,000 diverse treasures found within Nanhai No 1. Bamboo and wooden lacquers and the preserved remains of plants and animals have also been recovered from the ship.

The remains of the ship's body measure 22.1 meters long and 9.35 meters wide. Archaeologists believe it is one of the largest and best-preserved Song Dynasty oceangoing merchant trade ships ever discovered.

"The ultimate goal of all these protection efforts is to achieve long-term and safe preservation of the ship hull and unearthed cultural relics," said Wang.