Breakthrough as treasures from Titanic WWI 'sister ship' the Britannic discovered

Archaeologists have hailed a breakthrough after priceless relics were recovered from the Titanic's 'sister ship' over a century after it sank.

The HMHS Britannic was constructed as a luxury liner in 1914, but was requisitioned as a hospital ship when World War Ibroke out a few months later. However, just two years after its construction, it hit a mine and sank off the coast of Kea, southeast of Athens, while on its way to the Greek island of Lemnos.

The vessel, once the largest hospital ship at sea, vanished beneath the waves in less than an hour. The 1,060 passengers onboard managed to escape, but 30 tragically lost their lives when their lifeboats were hit by the propellers of the ship.

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This week, officials announced that artefacts have been recovered from the shipwreck for the very first time. According to Greece's Culture Ministry, an 11-member deep-sea diving team conducted a week-long operation in May to salvage artefacts from the wreckage in "tough" conditions.

Among the items retrieved from the liner - which was the third of the White Star Line company's Olympic steamships alongside the Titanic and the Olympic - were its bell, navigation light and plush fittings.

Divers closed-circuit equipment and battled against strong currents and poor visibility during the expedition, before bringing up a selection of remarkably well-preserved artefacts. It included the ship's lookout bell, silver-plated serving trays, ceramic tiles from a Turkish bath and a porcelain sink, believed to be from the second-class cabins.

The sink even retained its white finish, while a plate still displayed the bright blue stamp that read: 'White Star Line'. A navigation lamp and a pair of passenger binoculars were also recovered as part of the discovery effort.

The wreck of the Britannic lay undisturbed at the bottom of the Aegean Sea until December 1975, when it was discovered by deep-sea explorer Jacques-Yves Cousteau.

It was found lying at a depth of 120 metres (400ft), making it accessible to only the most skilled divers. The new recovery operation was jointly organised by British historian Simon Mills, founder of the Britannic Foundation. The artefacts have been sent to Athens for conservation.

They will then be included in a permanent collection of the new Museum of Underwater Antiquities, currently under development at the Greek port of Piraeus. The museum will feature a dedicated First World War section, with the items from the Britannic as a centrepiece.