The plaque in front of the monument read:

This monument is erected to commemorate the arrival of the first Japanese naval ship Kanrin Maru in San Francisco bay on 17 March 1860. The Kanrin Maru crossed the pacific at the same time as the U.S.S. Powhatan which brought the first Japanese Embassy to the United States. Presented to the City of San Francisco by its sister City Osaka as a token of its sincere desire to further strengthen the ties of friendship and goodwill between the United States and Japan and as part of the program to mark the Centennial celebration of the opening of their diplomatic relations.

17 May, 1960
This plaque presented by the City of San Francisco

The monument is a vertical black slab of stone with Japanese writing on it.

Front view of the monument which is a vertical black slab of stone with Japanese writing on it.

The monument when viewed form below and behind it.