For one week, a corner of London has been transformed into a pocket of ancient Japan, with dozens of sumo wrestlers descending on the city in a rare foray outside the sport's homeland. The Royal Albert Hall, world-renowned as a concert venue, is housing an authentic soil-and-sand dohyo, or wrestling ring, and a striking roof reminiscent of a Shinto shrine. It is the first time the Japan Sumo Association has staged an event outside Japan since 2013, when the wrestlers competed in Jakarta, and mar