A series of fourteen coastal defense guns, including four large Vickers 8-inch guns purchased during the Russo-Japanese War from the British, were secured in concrete bunkers around the island to guard the open water approaches.
Empat belas meriam pertahanan pantai, termasuk empat meriam Vickers 8-inchi yang dibeli saat Perang Jepang-Rusia dari Inggris, terlindung bunker beton di sekeliling pulau untuk berjaga dari pendekatan melalui perairan terbuka.