Bicycle touring was not on my radar when, while hitchhiking near Big Sur (California) around 1978, I met a British Columbian couple at a campground. They were bicycle touring south along the coast of California. I was intrigued.
Six months later, in 1979, while visiting San Diego, a friend took off on a transcontinental bicycle tour. Three months later, we rendezvoused in Toronto, and I was impressed he had made it all that way. I wanted to do the same. So I bought my first touring bike, a Motobenane.
Although I did uncounted day trips with my Motobecane (and after it was stolen, with a Miyata 1000), it took 19 years -- it was 1998 -- before I did my first multi-day bike tour in Alsace and Burgundy.
I've been hooked since.