(AFP) - Does the sea hold the secret to truly great wines? To find out a trio of French wine lovers -- a vineyard manager, a barrel maker and an oyster farmer -- teamed up to test the myth, above and below water. "I had heard a bunch of stories about wines ageing at sea," Bruno Lemoine, who runs the cellars of Chateau Larrivet Haut-Brion in the southwest Bordeaux region, explained as he unveiled their findings this week in Paris. One of the earliest known sea vintages dates from the 18th century, when the Bordeaux baron Louis-Gaspard d'Estournel sent a shipment of wine to India, whose unsold bottles returned to France mysteriously improved by the hull journey.