Chinese pagoda, itself an interpretation of the Indian stupa. Like the stupa, pagodas were originally used as reliquaries but in many cases they ended up losing this function. Pagodas are quintessentially Buddhist and an important component of Japanese Buddhist temple compounds but, because until the Kami and Buddhas Separation Act of 1868, a Shinto shrine was normally also a Buddhist temple and vice versa, they are not rare at shrines either. The famous Itsukushima Shrine, for example, has one.
Photo and text: Wikipedia