To wall off nearly 22-million Beijing residents from the risks of Covid-19 Winter Olympics athletes may bring with them, China has built a city within a city where no one can interact with those living outside, but where there is unrestricted internet access and meals served by robots.

Over two months, tens of thousands of athletes and support personnel are expected to enter the bubble for the Olympic and Paralympic Games, which spans parts of central Beijing, the capital’s outer Yanqing district and Zhangjiakou city in neighbouring Hebei province. They’ll move around in the “closed-loop” system between competition venues, hotels and even bars, connected by a dedicated transportation network...