Olszak pond - the last of the four reservoir ponds between lake Swarzędzkie and Lake Malta. It was created by damming the waters of the river Cybina. Nowadays has a function to slow down the flow the water and clean it before reaches Lake Malta. The pond and its surroundings are among the areas with high natural and landscape values . In order to maintain the Environmental Protection Department of the City of Poznan in 1994, created in this place ecological route "Olszak I".