The Daigokuden of Heian-kyo was directly connected with the Chodoin to the south, in contrast to its predecessors which were encircled by Tsukijikairo (a cloister along a surrounding clay fence) containing a Komon Gate (refer to the image: Plan of Chodoin).
平安京大極殿はそれ以前のものが築地回廊で囲まれ、閤門を持っていたのと異なり、南の朝堂と直接つながる構造となっていた（画像PlanofChodoin参考）。