sentences:  They are places without the daily stress of the professional life, usually places of quiet and calmness with profound positive emotional experiences that allow people to immerge into another world – even in the middle of busy cities.This therefore is also one of the many reasons why zoos are visited today by young and old by the millions.Zoos personnel know that this experience is possible only if visitors have the impression that the animals are healthy and well kept in naturalistic habitat-like enclosures.