In a frenetic race across the world, travellers can choose any route they like - but no flights or phones are allowed. On the trip of a lifetime, which pair will finish first?
Greenwich, London to Delphi, Greece
Delphi, Greece to Baku, Azerbaijan
Baku, Azerbaijan to Tashkent, Uzbekistan
Tashkent, Uzbekistan to Huangyao, China
Huangyao, China to Koh Rong, Cambodia
Koh Rong, Cambodia to Singapore