Jazz took me to New Orleans, Carnegie Hall and clubs in downtown New York; rock music shunted me from Sun Studio in Memphis, where Elvis, Johnny Cash and others recorded, through the doors of Abbey Road in London and to more clubs than I care to count; and blues took me to Clarksdale, Mississippi where I stayed in the run-down hotel Bessie Smith died in back when it was a hospital.
Curiosity about Chinese music had me on the back streets of Kunming in southwest China looking for a pipa (a lute-type instrument which I hadn't even touched, let alone thought I could play); country music had me at Loretta Lynn's antebellum mansion in rural Tennessee ("horses down that away" reads a sign), then on to Nashville. Tango took me into milongas (dance halls) in Buenos Aires and a past-midnight club for flat-tack punk-tango by the band Fernandez Fierro.
I've played washboard with a zydeco band in New Orleans (a real stretch of my abilities) and have sung tunelessly in a sleazy barrio bar in Madrid. I did worse karaoke in small-town Japan where my hosts were astonished I knew Japanese. I don't.
To learn the great jazz pianist Cedar Walton was playing in Paris meant a journey to a very cool arrondissement I previously knew nothing of and, afterwards, dinner with other chatty jazz lovers whom I would otherwise never have met. An Elvis fanatic's homage to The King in a small town in north Mississippi meant a short detour between Memphis and Tupelo. It was mad and I wouldn't have missed it for anything. I commend Graceland Too in Holly Springs to anyone - anyone with nerves of steel, that is.
I've been to the graves of Elvis (Memphis), Buddy Holly (Lubbock, West Texas), Jimi Hendrix (Seattle) and Jim Morrison (Paris). I stood where Jeff Buckley went for his last swim (the swirling Wolf River in Memphis) and where the Ramones, Talking Heads, Blondie and dozens of other bands played (CBGBs in New York).
Were all these interesting? Of course not, but it was in the getting there.
The point is, your passion can pull you away from the tourist trails and take you to parts of town others might never see.
Your interest may be ancient civilisations - boy, does Ireland have a treat for you at Newgrange near the River Boyne - or soccer (can anything beat a stadium game in South America for atmosphere?). It may be literature (most cities offer literary walks) or food (there are cooking classes everywhere).
By following your passion you'll invariably meet others sharing it (football hooligans don't frequent cooking classes in Hanoi) and so conversations begin, friendships blossom and reciprocal hospitality can be suggested. "You must look us up if you're ever in..."
This is what travel is about; people and things that interest and stimulate you. If you don't care about tennis at home, then Wimbledon is probably wasted on you.
My interest got me away from the pool in Bali and into villages at night to hear gamelan orchestras (sublime, incidentally) and drew me across the square in Marrakech to sit beside Berber musicians when it might have been easier to stay in the restaurant. What would I have gained if I'd had another mint tea? I know what I would have missed.
When we travel, it's easy to be seduced by the stately home, the architectural wonder, a Really Famous Painting... If that's your passion, then fine. But if it isn't?
Of course, we hear the call of the local market... but if you ain't cookin', you ain't buyin', so it's probably a waste of time. Use that time looking at dead fish and strange vegetables to do something you really want to do. You've paid heavily for it. And it isn't coming back.
