As structures made of brick are weak against earthquakes , the lighthouse was completely destroyed by the earthquake that occurred on April 26 , 1922 . The reconstruction of the lighthouse as a reinforced concrete structure was completed on March 15 , 1923 . However , the new lighthouse functioned for only six months before again being damaged by the Great Kantō earthquake of September 1 , 1923 ( magnitude 7.9 ) , the lighthouse was fractured with cracks and the top collapsed . Restoration work on the lighthouse was commenced on September 18 , 1924 and , on June 1 , 1925 , the present Kannonsaki Lighthouse was completed
Great Kantō earthquake
1923 Great Kantō earthquake
Kannonzaki Lighthouse