Yokohama is the second-largest city in Japan by population and by area, and the country's most populous municipality. It is the capital and most populous city in Kanagawa Prefecture, with a population of 3.7 million in 2023. It lies on Tokyo Bay, south of Tokyo, in the Kantō region of the main island of Honshu. Yokohama is also the major economic, cultural, and commercial hub of the Greater Tokyo Area along the Keihin Industrial Zone.

Keikyu Corporation , also known as Keihin Kyūkō (京浜急行) or, more recently, Keikyū (京急), is a private railroad that connects inner Tokyo to Kawasaki, Yokohama, Yokosuka and other points on the Miura Peninsula in Kanagawa Prefecture. It also provides rail access to Haneda Airport in Tokyo. Keihin (京浜) means the Tokyo (東京) - Yokohama (横浜) area. The company's railroad origins date back to 1898, but the current company dates to 1948. The railway pioneered Kantō region's first electric train and the nation's third, after Hanshin Electric Railway and Nagoya Electric Railway (Meitetsu) with the opening of a short 2 km (1.2 mi) long section of what later became the Daishi Line in January 1899.