Jotomyodai 常燈明台

There is a tower that resembles a lighthouse in front of the Tayasu Gate. It is called "Jotomyodai," meaning a tower of a ceaseless light. It was built in 1871 for the Tokyo Shokonsha Shrine, the forerunner of the Yasukuni Shrine, but as the light was visible from the Tokyo Bay and the Sumida River in those days, it is said to have served as an aid of navigation. The tower stands at the top of the Kudan-zaka slope, that lies between the low alluvial plain and the Yamanote terrace.

田安門の前に常燈明台というものがあります。明治４年に、東京招魂社（現在の靖国神社）の灯篭として作られたもののようですが、九段坂の上の良い場所にあったので、当時は船からも見えたそうです。

ネットでは、Lighthouse と書いているページもあるようです。