The sacred Japanese site, which bans women visitors and requires men to strip naked and follow a cleansing routine before stepping onto the island, cracked the nod from the World Heritage Committee for its tradition of worship.
Okinoshima is a tiny island below South Korea, that belongs to the city of Munakata in Fukuoka, Japan.
From the 4th to 9th centuries, large scale rituals were conducted on the island, during which prayers were performed for safe ocean voyagers, according to the Okinoshima Heritage website.
But visiting this attractive historical site is no easy feat.
Turning down advice by the International Council on Monuments and Sites (ICOMOS), a Unesco advisory body, to exclude four components, the committee chose to add all the eight components that the Japanese government had recommended to the cultural heritage list.
Around 80,000 items unearthed on the island have been designated as national treasures, reports said.
To be awarded World Heritage status a site must be of outstanding universal value and must meet one of the ten selection criteria. Men are allowed to visit once a year, on May 27, for a festival held to "comfort the spirits" of Japanese and Russian servicemen who died in battle in the Sea of Japan in 1905. They are told not to speak of their time on the island after they leave and are not permitted to take anything from the island.
There is little chance that the gender bar will be lifted after the island is included on the Unesco World Heritage list.
This July 8, 2017 picture shows a Shinto priest holding a ritural ceremony at Okitsugu shrine of the Munakata Taisha in Okinoshima island, some 60 kilometres from Munakata city, Fukuoka prefecture.
"Shinto treats blood as an impurity".
"We don't want people to approach the gods without due reflection", Ashizu said "We wouldn't open Okinoshima to the public even if it is inscribed on the UNESCO cultural heritage list because people shouldn't visit out of curiosity". The land is owned by Munakata Taisha, and it is a criminal offense to visit the island without the shrine's permission.