Keio Corporation is a private railway operator in Tokyo, Japan, and the central firm of the Keio Group that is involved in transport, retail, real estate and other industries.

Chōfu is a city in the western side of Tokyo Metropolis, Japan. As of 1 April 2021, the city had an estimated population of 238,087, and a population density of 11,000 per km2. the total area of the city is 21.58 square kilometres (8.33 sq mi).