The greatest feat of civil engineering since Roman times was the French achievement between 1666 and 1681 of the Languedoc canal to link the Mediterranean Sea with the Atlantic Ocean. It was conceived of by King Francis I and discussed by him with Leonardo da Vinci. It was first surveyed in 1539. As a result of the civil and religious disorders in France, however, nothing happened until 1661 when Pierre Riquet worked out a scheme for supplying enough water to the summit of the canal. Jean Colbert secured the interest of the young King Louis XIV, and in 1666 the work started. The whole canal was 150 miles long with 102 locks, a tunnel, and 3 aqueducts. It evoked world admiration, and was the prototype of all future European grand canal designs even though its usefulness to France was quickly nullified by the rapidly increasing size of ocean-going ships.