AIDA, Sho Click picture for larger image. Tournament Office : c/o The Keio University Tennis Club, 4-1-1, Hiyoshi, Kohoku-ku, Yokohama City, Kanagawa 223-8521, JAPAN E-mail : info@keio-challenger.com / Phone # : +81-80-1275-9120 / Fax : +81-45-562-2989