The marble sculptures are date back to the 2nd century, and are said to have much archaeological importance as creations from the Greco-Roman period. Among the discoveries are a figure of Venus and a bust of the Roman Emperor, Marcus Aurelius.

Veronica Robbins, from the Receiver of Wreck, which administers the wreck and salvage of ships in British territorial waters, described the return of the marbles to Turkey as "the end of one of the most extraordinary maritime archaeological stories in recent years".

Tombstones with inscriptions were also discovered

The marbles were stumbled across by British divers in 1994, while on a recreational dive to view the wreckage of the vessel, SS Castor.

The Glasgow-built ship sunk in 1894 after colliding with a German barque in dense fog off the Kent coast. No lives were lost and the wreckage itself only came to be offically located in 1977 in the coastal town of Dungeness.

Homeward bound

SS Castor had been carrying the marbles on behalf of the Dutch vice-consul in Smyrna, Turkey, who traded in antiquities despite Turkish legislation forbidding this.

It has been established that the marbles were part of a two-crate consignment bound for the Leiden Musuem in Holland. However, the second crate, containing another complete statue, has never been found.

On their discovery, much of the research into the indentification of the Castor marbles was carried out by the Canterbury Archaelogical Trust (CAT). Until their ownership was established, they were housed in the Folkestone Museum in Kent.

Discussions took place between the governments of Britain and Turkey, the latter of whom had claimed ownership of the marbles. This was upheld by The Receiver of Wreck, which administers the wreck and salvage of ships in Britain.

Historical significance

The value of the Castor marbles is estimated to be around £25,000, but their archaeological significance is a great deal more.

Research suggests this the young Marcus Aurelius

Richard Cross, who led the research into the identification of the marbles on behalf of CAT, said: "The sculptures are precious because they are of good quality and show a significant style and form.

"The bust of Marcus Aurelius has historical importance because it appears to depict the Roman emperor as a young man," he said.

The amicable settlement between Britain and Turkey concerning the ownership of the marbles also raises a reminder of the ongoing and as yet unresolved debate between Britain and Greece over the rightful home of the Elgin marbles.

The Elgin marbles are on display at the British Museum

These 2,500-year old sculptures were removed from the Parthenon in Athens by Lord Elgin last century, but for years the Greek government has been urging Britain to return them.

But Mr Cross says: "The story of the Castor marbles is unique in that the cargo of statues was part of the systematic looting of antiques from Smyrna to build up European collections.