“For two years following Japan’s defeat in August 1945, travel into and out of the country was strictly regulated by the Occupation forces; no foreign business travellers were allowed entry until August 1947, and inbound pleasure travel was forbidden until December 1947, when American tourists travelling to the Far East on board the liner President Monroe were allowed to disembark at Yokohama for twenty-four hours. While a tour of Tokyo was not allowed during this first postwar visit, these tourists visited Kamakura and the US Army base in Yokohama.
“The first tour that included Tokyo occurred in February 1948 when passengers aboard the same ship, the President Monroe, were permitted a one-week package excursion in Japan. In June 1948, the Occupation authorities announced that a single seven-day conducted tour each week for a maximum of twenty-four persons would be allowed for American visitors to Japan.”
– Japanese Tourism: Spaces, Places and Structures, by Caroline Funck & Malcolm Cooper, 2013