HOLD THE BOILING OIL!

James Wright. Historic Building Mythbusting; Uncovering Folklore, History and Archaeology. History Press, 2024

There's always a hidden tunnel, isn't there? Whenever you are being shown round some old mansion, castle, church or even there will be someone who tells you about the hidden tunnel.

Sometimes they are are dug by smugglers hiding their contraband, or thieves stashing away their booty. If you're very lucky they might reveal the resting place of the Holy Grail or the Ark of the Covenant – this one is in Burton-on-Trent if you want to go searching. Quite often it's a bit of ecclesiastical naughtiness, linking the monastery with the nearest pub - or convent.

Well it doesn't take much to disprove most of these legends. One reputed tunnel in the author's own county of Staffordshire, supposedly linking an abbey with a local mansion house, would have been nearly two miles long, in difficult tunnelling terrain, and also had to burrow under the River Trent. A task which, the author comments “would have troubled even the prowess of the Cornish tin-miners” of the time. And apart from anything else there would seem to be no particular reason for constructing such a tunnel in the first place.

But not all stories of hidden passages are completely false. A blocked-up archway in a cellar may not be the entrance to a secret tunnel, but may hide secrets of its own, which although not as romantic as some of the tunnel legends can be even more important archaeologically. They can reveal store-rooms, wells, mines, drains, even actual tunnels built for access and escape. But these are all relatively short.

A lot of tunnel-lore is attached to castles, but these raise other problems. What is a castle for? Well obviously it's a stronghold of the local earl or baron, defending his territory against other barons, the king or the rebellious peasantry. This involved lots of sword fights, often on spiral staircases which turned in a clockwise direction going upwards so that right-handed swordsmen would have more room to wield their weapons against attackers from below. Sounds logical, and we've all seen the films. Unfortunately actually examining the way staircases turn in castles outside Hollywood, there is no particular pattern, the orientation depending more on the structure of the castle, and its architecture.

It is a myth in itself that castles were the scenes of dramatic battles. in England at least they very seldom were, and they never hosted daring sword-fights between defenders and attackers. And you can forget about pouring boiling oil on attackers, oil was far too valuable for that.

Oh, and whilst waiting to be called into action, swordsman and archers have probably never sharpened the blades and arrowheads on the side of the parish church, leaving noticeable grooves in the stonework. The priest would not have liked that. The real reason for those grooves is a much stranger phenomenon. As is the real source of the strange burn marks found on the timbers of old houses. It is far more interesting than the conventional explanation of careless servants leaving candles burning unattended.

Even more surprisingly the sometimes rather obscene carving hidden away in churches were not put there by disgruntled craftsmen protesting over pay and conditions, but had the full authority of the clergy. Here you will find the very strange explanation of what was their real purpose.

And that emphasises something rather important about this book, it is not a 'debunking' exercise designed to show us how ignorant we are about history. The 'myths' are not just dismissed, they are carefully analysed, and the backgrounds to them unravelled, as usually they are based on actual historical evidence, which has been misinterpreted, by scholars and laymen, over the centuries. The story behind the myth is usually far more interesting and entertaining than the myth itself.

This is a book that will be enjoyed by anyone with an interest in history, combining a depth of scholarship with an accessible style. The author is a professional archaeologist and he gives interesting insights into what that entails, having worked with local councils and conservation bodies.

By the way, if you're looking for then oldest pub in England there are a number of possibilities, but rather depends on what you mean by a 'pub', or 'inn', or 'tavern' or 'hostel'. But whatever, it's almost certainly not one that calls itself 'the oldest pub in England'. It seems the answer is all in the trees. Dendrochronology is your friend.

Film director John Ford is reputed – wrongly – to have said “when you have to choose between history and legend, print the legend.” This book demonstrates that invariably the history is far more interesting than the legend.

• Richard Samuels