Photo taken in 1955 (Showa 30) - 4 years after Japan signed the San Francisco Peace Treaty which made Japan an independent country again.
In many of these photos you will notice the clock tower - its the Hattori Clock Tower which originally stood from 1894 to 1921. It was demolished in 1921 to rebuild a new one but reconstruction was delayed due to the Great Kanto Earthquake. The new clock tower was completed in 1932 (Showa 7).
The clock tower was built by Hattori Kintaro who was the founder of the company which was to become of of the largest watch makers in the world - Seiko.