Already China has built a new road, giving its landlocked Jilin and Heilongjiang provinces efficient access to Rajin, Asia's most northerly year-round ice-free port.

ECONOMIST: Letters

St Petersburg owes its popularity to its ice-free port, good rail links and well-educated workforce, as well as the can-do approach of the governor, Valentina Matviyenko, who has promised to turn the city into Russia's Detroit.

ECONOMIST: Theme and variations