Edited sentence: Among other donors, the Swiss retailed Coop usually sponsors also a small snack and a drink to visitors free of charge or to a reduced price.Among the attractions are several meeting points where every half hour zoo officials give insights of the meeting points exhibit and animals that live in it.July 23rd:  In memory of Peter Sauter, a major donor to the zoo, entry to the zoo is free of charge on this day.Zolli night: Once every summer the zoo stays open until midnight