Newly-launched Map World contains a few howlers, including the new English towns of Ostrow Wielkopolski and Bashmakova

Polish now forms part of the rich cultural hotchpoth that has given Britain its peculiar placenames, according to an erratic Chinese government internet map that places a town called Ostrow Wielkopolski just south of Watford.

The Polish town is just one of several mysterious additions to the map of Britain by Map World, a service launched this week to help Chinese internet surfers navigate their way around the globe in English.

Drivers using Map World to seek a route from north Wales to Chester, however, might be surprised to find themselves expected to go via a place called Bashmakova. And the road from Darlington to Middlesbrough goes by a mysterious new town called Chishmy.

The latter name, when Googled, turns out to belong to a town with a pretty Orthodox-looking church in the Republic of Bashkortostan on the southern fringes of the Russian Federation. Chishmy lies 40 miles west of Bashkortostan's capital, Ufa.

The new places the Chinese have added to Britain are, in fact, foreign towns and cities that have somehow slipped across the globe.

Bashmakova, for example, sits astride a main railway line 300 miles south-east of Moscow. The real Ostrow Wielkopolski lies south of Poznan and west of Lodz.

More difficult to explain is the new London neighbourhood of Unk, which apparently lies on a bend in the river Thames beside Richmond Park. It does, at least, have some natural twin towns dotted around the world as Map World places another Unk in Spain, four in Australia, three in Africa and two in Latin America.

Google Maps registers only three Unks. Two lie just 30 miles apart in Iranian Kurdistan and in the Iraqi province of Suleiminya. The third is a cul-de-sac near the airport in the Liberian capital of Monrovia.

These are not the only mistakes. Not far from Tyneside, you'll find the previously unknown English towns of Almenevo and Mar'yanovka.

But sensitive Britons should not feel they have been singled out. Spaniards have discovered that the north-western port of Ferrol has been returned to the days of General Francisco Franco, Spain's dictator or "caudillo". He had his birthplace renamed El Ferrol del Caudillo. That name was removed in 1982 but remains on Map World.

Map World launched on Tuesday after a three-month trial. About 30 million users had visited in that time, according to Min Yiren, the deputy director of China's State Bureau of Surveying and Mapping.

"We'll make greater efforts to build Map World into an international brand," Yiren said, according to People's Daily Online.

Map World contains 11m place names. Can anyone spot more howlers?