The nine-kilometre-long Oosterscheldekering (kering meaning barrier) was initially designed, and partly built, as a closed dam, but after public protests, huge sluice-gate-type doors were installed in the remaining four kilometres.
At the artificial island Neeltje-Jans, at one end of the barrier, a plaque is installed with the words: "Hier gaan over het tij, de wind, de maan en wij" ("Here the tide is ruled by the wind, the moon and we (the Dutch)").