The Tierpark Hagenbeck is a zoo in Stellingen, Hamburg, Germany. The collection began in 1863 with animals that belonged to Carl Hagenbeck Sr. (1810–1887), a fishmonger who became an amateur animal collector. The park itself was founded by Carl Hagenbeck Jr. in 1907. It is known for being the first zoo to use open enclosures surrounded by moats, rather than barred cages, to better approximate animals' natural environments.

A moat is a deep, broad ditch, either dry or filled with water, that is dug and surrounds a castle, fortification, building, or town, historically to provide it with a preliminary line of defence. In some places moats evolved into more extensive water defences, including natural or artificial lakes, dams and sluices. In older fortifications, such as hillforts, they are usually referred to simply as ditches, although the function is similar. In later periods, moats or water defences may be largely ornamental. They could also act as a sewer.