The main dike, Ellenser Damm, was built between 1596 and 1615 by the County of Oldenburg before the agreement with the objecting County of East Frisia was finished successfully.
Peamine tamm, Ellenser Damm, ehitati aastatel 1596 kuni 1615 Oldenburgi krahvkonna poolt enne kokkuleppe edukat lõpetamist vastuvaidleva Ida-Friisi krahvkonnaga.