Never mind the architecture — what’s it made of? The Geology of Oxfordshire (Dovecote, £10) will tell you.

Philip Powell is the perfect author, having spent 40 years as assistant curator of the geology collections at Oxford University Museum of Natural History.

And it’s ideal for the general reader, with a helpful glossary. The book is arranged chronologically, and there are maps and photographs allowing you to visit spots of particular interest — although he says that apart from the cement quarry at Kirtlington, the other geological sites where you might find fossils are all on private land.

But it’s easy to see the red fields of Banburyshire, the marlstone and limestone used for village buildings at Deddington — or to visit the William Smith monument at Churchill, near Chipping Norton, dedicated to the father of English geology. Then there is Taynton stone, from the hamlet near Burford, used to build Windsor Castle, several Oxford colleges and churches — and on Radcot Bridge, north of Faringdon.

As for the Radcliffe Camera, above, the situation is complicated. Headington limestone has decayed badly in Oxford’s damp atmosphere, says Powell. The white plinth at ground level and at the base of the columns is a more durable variant called Headington Hardstone. The walls and columns at the top were originally Taynton Stone but have been patched with other stones.