I've always confused Jerome K. Jerome's Three Men in a Boat with the nursery rhyme "rub a dub dub, three men in a tub". Knowing little of either, it took me years to realize they were different things. I thought I should make the effort to actually read the novel, once I realized there was one.
The book is much funnier than I anticipated, though it has its weak spots as well. The main conceit is a conceited, unreliable narrator. He and his fellows frequently err, though the errors are described in a dry tone that pretends to be reporting success (at least on the part of the narrator). It's very well done, and the result is not only witty but occasionally laugh out loud funny.
Occasionally, Jerome allows himself to be distracted by detailing the cities and sites they pass through, rendering the book less novel than travelogue. Wikipedia tells me it actually went the other way - originally intended to be a travel guide - in which case its success as comedy is even more surprising (though it suggests that the sappy, serious sections, were not intended to be overwritten). Even allowing for the travel guide, there's a long middle section on a historic battle that the book would have been better without. The book never really goes anywhere - the three men (and the dog) take their two week trip, and then they go home - but the trip is a fun one.
The book is dated in social attitudes (race, gender), but the great bulk of the humor holds up well. The version I read suffered from Open Road Media's often lackadaisical approach to proofreading.
Overall, a fun and funny book, worth reading.