Blenheim Palace is the only World Heritage Site in Oxfordshire. But how many officially-designated heritage sites are there in Britain?

That was the question posed by the sons of publishers Victoria Huxley and Geoffrey Smith. After guessing five or six sites, including Stonehenge, they were stumped.

Now they have set out a very comprehensive answer in World Heritage Sites of Great Britain & Ireland (Chastleton, £12.99.

They try to explain why each site was chosen by Unesco — was it unique in some way, or the first of its kind in the world, or was it important in history?

If you follow their journey, you will find yourself visiting tourist attractions like Bath and Canterbury, but also Cornish tin mines and Welsh coal seams.

Britain was the home of the Industrial Revolution and the architecture of our poorer ancestors can be just as interesting as that of the rich.

Then there are the natural landscapes of Dorset’s Jurassic Coast, the Orkneys and Giant’s Causway in Northern Ireland.

It’s an attractively produced book with lots of useful information, particularly on how to get to the sites by public transport.