What a kōraimon is
A kōraimon carries a gabled roof over its main posts and adds smaller roofs, set at right angles to the first, over the supporting posts behind. Where a Yakuimon covers both pairs with a single roof, this form divides the roof into three and keeps each part small.
The small roof has a purpose. At a castle the gate stands at the outer side of a Masugata, and cutting the roof back leaves a line of sight and of fire down onto anyone who has entered.
The structure field records it briefly. A gate at Honganji in Kyoto is entered as a single-bay gate of this form, Kirizuma-zukuri, with flanking walls to north and south, under Hongawarabuki.
The great gate at Hongakuji in Kanagawa Prefecture, from the early Showa period, is described as opening onto the lane north of the main hall, a single-bay gate of this form without doors, gabled and pantiled, with flanking walls on both sides, round main posts tied by a beam with the purlin carried on two tiers of shaped brackets, and the flanking walls boarded at the base with vertical lattice above. The entry calls it a heavy-timbered gate that gives the temple its standing.
Distinguished from the yakuimon
The roof decides it. A yakuimon has one gabled roof spanning both pairs of posts, its ridge set forward over the main pair. This form roofs the main posts and then adds a separate crosswise roof over each supporting post. Looking above the rear posts settles the question.
Some have no doors at all. The Hongakuji gate omits them, so passage is always open; the gate marks the boundary of the precinct rather than closing it.
Sodobei usually accompany it. Short walls run out to either side to define the plot, so that the gate does not stand alone, which is why the Honganji entry names them.
On site, look above the rear posts. A small roof set crosswise there identifies this form; nothing above them indicates a Munamon, and a single roof spanning everything indicates a yakuimon.
References
- Agency for Cultural Affairs: National Treasures and Important Cultural Properties (structures)
- https://www.bunka.go.jp/seisaku/bunkazai/shokai/yukei_kenzobutsu/kokuho_bunkazai.html
- National Cultural Properties Database: Honganji, a single-bay Korai gate with flanking walls
- https://kunishitei.bunka.go.jp/bsys/maindetails/102/00004771
- National Cultural Properties Database: Hongakuji great gate, a Korai gate without doors and with flanking walls
- https://kunishitei.bunka.go.jp/bsys/maindetails/101/00014339
- National Cultural Properties Database: Inaba Residence gatehouse, carrying fire walls on the roof as a mark of the family's standing
- https://kunishitei.bunka.go.jp/bsys/maindetails/101/00003111
Last verified: 2026.09.11