"Water from the Mediterranean should take the place of a flame traditionally used in the Olympic Games," suggested Carlos Pardo, a journalist in Barcelona. 

"It will be water, pure clear water from the Mare Nostrum that will fulfill the mission, announcing to all that the Mediterranean Games is taking place in a spirit of peace and goodwill under the emblem of sport."

Pardo was part of a "golden circle" of friends of Juan Antonio Samaranch, the future President of the International Olympic Committee (IOC). Back then, Samaranch was still a national official and at short notice had become a major force in organising Barcelona's Mediterranean Games.

Pardo had first proposed his scheme in an article for the magazine Destino. He described the Games as a "Mediterranean meeting of the nations bordering on this Opening Ceremony with a pure Mediterranean flavour".

He envisaged the Ceremony would incorporate the arrival of vessels from Greece and a dramatic performance of music.

"On a beautiful site are preserved some Greek ruins that serve as a framework in a unique spot for the handing of an amphora of water to the first runner who will start his race with it towards Barcelona," he said.

When the Relay was was announced publicly in mid October 1954, the Organising Committee insisted it "would be in accordance with the character of the Games".

The Andalucian edition of the prominent newspaper ABC described the idea as "an emotive and symbolic ceremony" and La Vanguardia, another Spanish paper, called it "a happy idea".

Crucially, it also had the approval of the IOC. They were particularly worried about the proliferation of Torch Relays.

Games organisers briefed Otto Mayer, chancellor of the IOC, when he visited the city for the Roller Hockey World Championships in 1954 and he made no objection.

It was calculated that 200 runners would be needed to carry the amphora on its entire journey.

"It would be very fine and moving if the Relays across Barcelona be run by old and celebrated aces from among our sportsmen, such as those who have given a history, a continuity and an international repute to Spanish sportsmanship," it was said.

The night before the Games were to begin, a ceremony was held at Empuries, north of Barcelona, with a backdrop of the site where the first Greek settlers had made landfall in ancient times.

The dignitaries included the Marques del Castell Florite, President of the Barcelona Parliament, Pere Bretcha, his counterpart for Girona and IOC vice president Armand Massard from France.

They paid tribute to Baron De Guell, who had been an influential figure in the early years of Barcelona's preparations.

Half an hour later, the first bearer Alberto Gurt arrived, who stooped at the water's edge. Gurt was in fact a race walker who would compete in the Games a few days later.

The second runner was another athlete, Martin Amiel from nearby Figueras. He took the amphora to the museum where it was placed until its departure to Barcelona under a ceremonial guard.

"This ceremony perfectly fitted the traditions of the Olympics," wrote Michel Clare in the French sports newspaper L’Equipe, himself an 800 metres silver medallist at the inaugural Mediterranean Games in 1951. 

"The ceremony will remind us of how these Games for the nations bordering on the Mediterranean reflect the Olympic Games themselves."

Pardo's original plan had called for an artistic celebration and that night there were readings from the poetry of Pindar and a performance of The Trojan Women by Euripides. During the Games themselves, organisers made sure that cultural and artistic events were prominent alongside the sport.

The Games opened on July 16, 1955 and the first runner set off at 5.30am at the start of a journey of some 170 kilometres to Barcelona.

By 9am that morning it had reached Girona and by late afternoon it had arrived in Barcelona and was taken along Las Ramblas, the thoroughfare leading to the port.

When the Relay made its way to the Montjuich Stadium on the hillside above the city, it was taken by 110m hurdler Sebastian Junqueras who completed a lap of the stadium. 

"I did not feel any emotion when I entered the stadium because I tried not to allow myself to think of anything else so that I would not allow the amphora to fall to the ground," he admitted later. 

"When it was over, I felt satisfaction at the completion of a mission entrusted to the athletes in this symbolic act by Spanish sport."

A water fountain had been built on the platform between the statues in what Pardo described as a "vast luminous cascade" and Junqueras climbed to the top before setting the fountain in motion with his water.

The future IOC President Samaranch was delighted.

"Without changing the essential Olympic protocol, the Games brought a new idea, a new symbol to a brilliant realisation," he said.

"The waters flowed throughout the Games until the Closing Ceremony when the jet extinguished slowly, closing days which had been of the greatest human and sporting interest."

Pardo was also involved in running the Mediteranean Games in 1955 and his idea of the amphora was continued at future Games. 

When the runner arrived at the Opening Ceremony of the 1963 Games in Naples, Santiago Garola, the correspondent for La Vanguardia described how "my good friend and colleague Carlos Pardo could not disguise his emotion at seeing his original idea enacted again".

By the time the Games returned to Spanish soil in 2005, the amphora was long gone. It is believed it went missing at about the time of the 1975 Mediterranean Games in Algiers. There is speculation that it has fallen into the hands of a private collector.

When Barcelona's Olympic Museum was opened, Samaranch gave an interview to the Catalan newspaper El Periodico expressing his regret that the collection did not have the original amphora.

A reward of €6,000 (£5,200/$7,000) was posted but no information was forthcoming.

"It was very beautiful and very valuable," said Juli Pernas, director of the Fundación Barcelona Olímpica who researched the story of the amphora for his book on the 1955 Games. "We would love to have it, but it would be very difficult."

Although the vessel has never been found, its legacy for sport in Barcelona remains a strong one. Many of the sports competitions now staged in the city use the amphora as a trophy for the winners.

In 1985, a greying Gurt stood at the water's edge once more to collect water for a ceremony to commemorate the 30th anniversary of those 1955 Mediterranean Games. The symmetry was complete when Junqueras emptied the water into La Font Magica at Montjuich.

It was a celebration which gave added momentum, were it needed, to Barcelona's bid for the 1992 Olympics. In the event this proved unstoppable.

Seven years later on a sunlit evening, a flotilla of more than 300 sailing boats accompanied the Olympic flame as it arrived in Empuries, where Organising Committee President and Barcelona mayor Pascall Maragall was waiting to greet it .

"It will light the future of our people, purify our ideals, and warm Barcelonans, Catalans and Spaniards alike," he said. "We have waited for this moment for such a very long time."

The Games themselves proved supremely successful and were devoid of the political problems which had plagued the Olympic Movement for much of the previous two decades.

The organisers of Tarragona 2018 may well wish for the same result.