One of the largest grassy steppes in Europe, the Hortobágy was once a mosaic of open floodplains, swamps, loess and saline steppes, grasslands and forests. The landscape was mainly shaped by the relocations and floods of the Tisza and its tributaries, the grazing of large herbivores and the forests and steppes that were occasionally run by fires. The swamp world of Egyek-pusztakócs once covered almost ten thousand hectares, on the border of Ohat - Egyek - Tiszafüred. The long, north-south, flooded ancient swamps received the vast body of water from the Tisza floods as a natural reservoir, gradually draining the water through the southern swamps of Hortobágy, the Zádor River and the Körös-Berettyó water system. The topography of the area is much more varied than that of Hortobágy, which lies to the east of the swamp world. Surface shapes everywhere bear traces of the work of river water. In the long-lasting basin of the Kis-Jusztus swamp, for example, it is easy to recognize the bed of the Tisza or its former tributary, which is bordered on the east by a reef, the belt reef of the old watercourse, several meters apart.