High Quality Content by WIKIPEDIA articles! Dieppe is a commune in the Seine-Maritime department in France. In 1999, the population of the whole Dieppe urban area was 81,419. A port on the English Channel, famous for its scallops, and with a regular ferry service from the Gare Maritime to Newhaven in England, Dieppe also has a popular pebbled beach, a 15th-century castle and the churches of Saint-Jacques and Saint-Remi.