RIOJA-3 was a submarine telecommunications cable system linking the Belgium and the Netherlands across the southern North Sea.
It had landing points in: Oostduinkerke-Bad, Flanders, Belgium Egmond aan Zee, Netherlands
It was withdrawn from service on 13 October 2006http://atlantic-cable.com/Cables/CableTimeLine/index1951.htm, Atlantic Cable Cable Timeline, 1951-2000.
References
Sources Kingfisher information site FreeLibrary article