Artefacts from two historical shipwrecks, both centuries old, were excavated from Singapore's waters from 2019 to mid-2021.

Holding a wealth of Chinese ceramics, the ships were found in the waters near Pedra Branca in 2016.

According to Unesco, there are an estimated three million shipwrecks across the ocean floor. With only an estimated 5 per cent of the world's seabed mapped at high resolution, the watery depths hold untold troves of treasure.

Here is a look at notable shipwrecks found in the region and beyond.

1. Tang Shipwreck (found in 1998)

Carrying a cargo of ceramics produced in the Tang dynasty (618-906) and objects made of gold and silver, what is now known as the Tang Shipwreck was found off Belitung Island, east of Sumatra, in 1998. The ship, which had been bound for the Middle East when it sank/went missing, stands as a hallmark of trade between China and the Middle East, as well as the significance of South-east Asia as a trading hub. Objects excavated from the shipwreck are displayed in a permanent exhibition in the Asian Civilisations Museum.

2. Indian Ocean shipwrecks (2015)

The discovery of the sunken remains of two still unidentified ships in the Indian Ocean in 2015 was significant due to the circumstances of the discovery. The wrecks were found during the search for the ill-fated Malaysian Airlines flight MH370 that disappeared en route to Beijing from Kuala Lumpur. The plane has yet to be found, but more headway has been made with the ships - based on historical records, archaeologists have managed to narrow down their identities to a few coal-carrying British vessels.

3. Suspected USS Grenadier shipwreck (late 2019)

A team of divers found what they believe to be the wreck of a World War II US Navy submarine, the USS Grenadier, around 80m underwater in the Strait of Malacca. While the US Navy's Underwater Archaeology Branch has yet to confirm the identity of the wreck, the submarine holds the promise of opening a chapter in the history of WWII in the region.

4. Nanhai One (1987)

As one of the oldest shipwrecks to have been found in the South China Sea, the Nanhai One is emblematic of the scale of trade and commerce along the Maritime Silk Road. Thought to have been carrying 60,000 to 80,000 pieces of precious cargo when it sank, the Southern Song dynasty (1127-1279) vessel is also unique in how it was excavated and put on display. Using a variety of rigs and cranes, the shipwreck was raised whole from the seafloor before it was transported to the Maritime Silk Road Museum of Guangdong, in Yangjiang, China. Visitors can see archaeologists still at work underwater in the museum, where the wreck remains submerged in a pool-like container mimicking the conditions where the wreck was found.

5. Titanic (1985)

Ostensibly one of the most famous shipwrecks in popular culture, the Titanic shipwreck has managed to withstand the test of time since it met its unfortunate demise in 1912. Despite many artefacts being brought up to the surface and auctioned off, the wreckage itself remains underwater. However, this may not be the case for long. A team of divers filmed the wreckage in high-definition to help researchers assess the state of the structure in 2019. Based on estimates, researchers think that bacteria eating away at the iron in the structure will lead the disappearance of the wreck by 2030.