When the temperature in winter drops below 10 degrees, the king penguins in Zurich Zoo are taken for a walk.
The half hour walk from the bird's enclosure to the "elephant house" and back is an important distraction from daily zoo life, and an additional attraction for visitors.
There are currently 14 king penguins in Zurich, and all but two have come from other European zoos. Zurich's breeding programme has had moderate success. More than 20 chicks have been hatched since 1992.
After the emperor, the king is the second largest penguin in the world, standing up to one metre high and weighing about 15 kilogrammes. But they are easy to tell apart. The king penguin is slimmer, has a longer bill and more orange colouring on the breast.
At home in the Periantarctic and Subantarctic islands, they live in colonies made up of about 10,000 animals. They are able to dive at least 300 metres under water in search of fish and crustaceans.
The stroll at Zurich Zoo begins at 1.30 pm on suitable days. The zoo updates information about the walk and weather conditions on its website.