Three young, upper-middle-class men believe they are working too hard - though there is little evidence of this being so. They agree they need "rest and a complete change". They decide on a boat trip. They tow - from riverside towing paths - and row their craft up the Thames River from near Hampton Court to Oxford - and part of the way back.

Much of the humour is slapstick. Inanimate objects are given human characteristics. A can of pineapple defies all their attempts to be opened in the absence of a can opener. Fixing iron hoops over the boat - to support a canvas cover - causes problems.

Cooking failures, more than successes, are another source of amusement. "Cold veal pie, when you don't feel hungry, is apt to cloy", and the advantage of an Irish stew being that "you got rid of such a lot of things".

In the course of the journey, there are many humorous digressions into a variety of subjects: the Hampton Court maze, swimming in the surf, weather forecasting, the odour of cheese, school days, bagpipes, sea-sickness, fishing and fisherman, singing at parties.

The journey is also a tour of historic sites. The history is included in an informal non-academic way. The starting point is given as Kingston - which was known as Kyningestun "when Saxon 'kings' were crowned there". A suspiciously large number of pubs boast that Queen Elizabeth I had enjoyed overnight accommodation at their premises. Julius Caesar had "a camp, or entrenchment, or something of that sort" at Walton. And there's an "old priory that Henry VIII is said to have waited for and met Ann Boleyn".

In a battle at Reading, King Ethelred and his brother Alfred defeated the invading Danes - "Ethelred doing the praying and Alfred the fighting". And, ominously, "Parliament generally rushed off to Reading whenever there was a plague at Westminster".

The scene of the Barons forcing King John to sign Magna Carta is re-created when the travellers visit Magna Carta Island and see "the stone...on which the great Charter is said to have been signed". There is a suggestion that had a Richard been king, he would not have signed and "the cup of liberty might have been dashed from England's lips".

For most of the journey the three men are very critical of steam boats using the river. They go out of their way to obstruct them. However, they gratefully accept the offer of a tow from one of these boats and are then critical of small man-powered craft impeding their progress.

A sobering note is the finding of a woman's body in the river. This prompts a story of the tragedy of "a fallen" woman.

On arrival at Oxford, the travellers hire another boat and begin what they anticipate will be, a leisurely drift down the river to home. But it starts to rain. It continues to rain. Initial observations that they liked "to see the river under all its aspects" soon changes to "it's a pity we've made up our minds to stick to this boat". They don't. They leave the boat and catch a train back to London.

The three men have similar characters. They are selfish, intolerant, argumentative, fussy, lazy and openly critical of each other. A much more likeable character is the author's dog, Montmorency.

The full title of the book is Three Men in a Boat - To say nothing of the dog. Montmorency is a fox terrier. "Fox terriers are born with about four times as much original sin as other dogs." His ability to annoy his unlikeable owners endears him to readers. "Montmorency's ambition in life is to get in the way and be sworn at. If he can squirm in anywhere where he is particularly not wanted, and be a perfect nuisance, and make people mad, and have things thrown at his head, then he feels his day has not been wasted." When the Irish stew is being prepared, Montmorency appears with a dead water-rat in his mouth "to present as his contribution to the dinner".

In the BBC movie of Three Men in a Boat (1975) the dog portraying Montmorency is not a fox terrier. The movie immediately loses credibility. Montmorency in the 1956 movie of Three Men in a Boat is a fox terrier, and is accordingly more credible. However, neither movie can match the book, which cannot be effectively translated to the screen.

When first published, Three Men in a Boat was panned by the critics, as "vulgar", "uneven", "sentimental", "disrespectful". The public thought otherwise; it has never been out of print. It has featured in a 2003 Greatest Novels of All Time listing. For armchair travellers, maps of the route showing places visited are available online. Not only is the book still widely read, but today, 131 years later, people are still retracing the journey of those three men and their dog.