Hamaguri-Gomon Gate (蛤御門)
The Hamaguri-Gomon Gate is one of the west gates of Kyoto Gyoen National Garden. The official name of the gate originally was the Shinzaike-Gomon Gate. The gate is a sujigane-mon (iron girder gate) of the Korai-mon Gate style.
The gate came to be called by its nickname Hamaguri-Gomon Gate because it was the gate that rarely opened, but it opened like a hamaguri (clam) when the imperial palace burned in the Great Kyoto Fire of the Tenmei period during the reign of Emperor Kokaku. It's name ended up being official. The gate was the defense base for the Aizu, Kuwana, and Satsuma allied clans during the Conspiracy of Hamaguri-Gomon Gate, and the gate still has bullet holes made at the time.