The Osun Osogbo festival is held in Osogbo, Osun state, southwest Nigeria, it is to celebrate a river goddess, Osun. The groove covers 75 hectares of ring- fence forest, alongside the Osun river in the outskirts of Osogbo town, western Nigeria. The groove in Yoruba cosmology is the domicile of oosun, the goddess of fertility.

Osun is the Yoruba personification of the ‘water of life’ and the spiritual mother of Osogbo Township. It is a scared forest. Said to be and believed by some of its worshipers as the residence of the fertility goddess. Osun, the forest itself is full of shrines, works of art, sanctuaries and sculptures. The bulk of these offering are devoted to Osun, but many exist in reverence of other deities within the Yoruba pantheon as well. Within osun it is the sacred groove, an area of immense spiritual importance. The goddess is said to give properity and protection to her people if they built a shrine to her and respected the spirit of the forest.
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