Wikipedia
(also spelled Kan'eiji or Kaneiji) is a Tendai Buddhist temple in Tokyo, Japan, founded in 1625 during the Kan'ei era by Tenkai, in an attempt to emulate the powerful religious center Enryaku-ji, in Kyoto. The main object of worship is .
It was named in a reference both to the Enryaku-ji's location atop Mount Hiei (Tōeizan means "Mount Heiei of the East"), and also after the era during which it was erected, like Enryaku-ji (named after the Enryaku year period). Because it was one of the two Tokugawa bodaiji (funeral temple; the other was Zōjō-ji) and because it was destroyed in the closing days of the war that put an end to the Tokugawa shogunate, it is inextricably linked to the Tokugawa shoguns.
Once a great complex, it used to occupy the entire heights north and east of Shinobazu Pond and the plains where Ueno Station now stands. It had immense wealth, power and prestige, and it once consisted of over 30 buildings. Of the 15 Tokugawa shōguns, six are buried here.
Many temple structures were destroyed in the great Meireki fire of 1657. A new hall was constructed inside the enclosure of Kan'ei-ji in 1698. The temple and its numerous annexes were almost completely destroyed during the Boshin War's Battle of Ueno and never restored. Much of the site where it once stood was confiscated and is now occupied by Ueno Park.
What is today the temple's main hall was taken from Kita-in in Kawagoe ( Saitama Prefecture) and transferred to the site of a former Kan'ei-ji subtemple. Kan'ei-ji's five-story pagoda (photo above) and the Ueno Tōshō-gū shrine were amongst the gems of the old temple enclosure. Both stand undisturbed by the passage of years since the end of the Tokugawa shogunate.
The Shinobazu Pond itself and the Bentendō Temple which stands on its island used to be an integral part of Kan'ei-ji. Tenkai, liking Lake Biwa, had Benten Island built in imitation of Chikubushima, and then the Bentendō on it. At the time the island was accessible only by boat, but later a stone bridge was added on the east, making it possible to walk to it. The Bentendō Temple was destroyed during World War II, and the present one is a reconstruction.