ISTANBUL, TURKEY - AUGUST 08: A kitten looks out from a cat house in a park on August 8, 2018 in Istanbul, Turkey. Istanbul is known as the City of Cats and sometimes referred to as 'Catstanbul.' Hundreds of thousands of cats have roamed the metropolis for thousands of years. The city's streets are lined with food and water bowls and small cat houses placed by residents in a communal effort to look after the street cats. In Islam cats are considered ritually clean animals and the only animal to be permitted to enter the Great Mosque of Mecca and there are many stories in the history books referencing the Prophet Muhammad's love of cats. In 2016 a documentary film "Kedi" meaning cat in Turkish, which followed the daily life of a group of cats in the city grossed more than four million USD at the box office making it one of the highest grossing foreign language films to date. August 8 is International Cat Day. (Photo by Chris McGrath/Getty Images)