The Kumano shrines are shrines that are located in the southern part of the Kii peninsula. These shrines are meant to enshrine the many Kumano gods and represented an important pilgrimage site for aristocrats during Japan's classical age, including that described in the Tale of the Heike. Later, they also became a popular destination for commoners as well.There are three shrines included in this complex: Hongu, located in the central mountainous region of the central Kii peninsula; "Shingū," located on the eastern central shore of the peninsula, and "Nachi", located south along the shore from Shingū. The entire area bounded by the pilgrimage routes to them, referred to as the Kumano kōdō ("Old route to Kumano), was designated as a UNESCO World Heritage Site in 2004.
In The Tale of the Heike, the Kumano deities and Buddhism were mentioned many times through out of the story. The Kumano deities in specific were mentioned in the 15th chapter of Book Two, “Yasuyori’s Prayer” and the 16th chapter of book two titled, “Stupas Cast into the Sea”. In this chapter, Yasuyori and Naritsune travel across Kikaigashima and plot out a miniature Kumano pilgrimage route on the island, naming landmarks for places at Kumano, effectively recreating the sacred space of Kumano on the desolate island landscape of Kikaigashima. Kumano also figures prominently in Book Ten, which recounts Koremori's journey there to take the tonsure and eventually commit suicide.
Sources:
[1] "Kumano Kodo".Tanabe City Kumano Tourism Bureau Official site.www.tb-kumano.jp. 23, April 2018.
[2] "Kumano Sanzan".Tanabe City Tourism Bureau Official site.www.tb-kumano.jp. 23, April 2018.
Additional Information on Shrines, History, and Travel Routes [1]