The first century that I did was in 1991 in Manteca, California. I found a "Complete" book of cycling, can't remember who by, and decided 100 miles was a challenge. I followed a plan building up to 30, then 50 and then 75 miles. All went well until the 75 miler. Then I struggled. I had not yet learned about hydration or feeding on the bike, so I would stop at the library that had an outdoor fountain. By mile 60 water never tasted so good. I don't remember eating anything, though looking back, I must have. I did not carry anything with me, and if I had it would have been a sandwich. I don't recall there being GU back then. I also had not learned that there were reasons for wearing cycling kit. I was wearing cutoffs, t-shirt, no helmet, and tennis shoes.
Two weeks following the 75 mile ride, I moved on to the century. The route I was following was a 4 mile square block. The plan ( I can't believe it myself now) would be to ride the square 25 times. Is it possible that I miscounted? I don't know. There also were not cyclcomputers at that time either. This brings up an interesting point. Here I am in the year 2015, having X number of miles, Y number of centuries, and the accuracy over 25 years cannot be 100%. And it really doesn't matter. It's not about a number, it's not about personal bests, it's not about whether I won or not. It's about doing something so many times, for such a long time that it questions our definition of what is possible. I am 68 years old, and still doing century after century. In 1991, most people, including exercise physiologists did not believe this to be possible. And while there is no question that I have slowed down, I am still riding at about the same level as 5 years ago, and at a much higher level than 1991.
I did that 25 times around that square in Manteca. I remember stopping every four or so loops at the library, sometimes drinking like a dog. I remember it was hot. I remember stopping halfway, at home, to stuff myself with two sandwiches. I remember how tired I was during the last 25 miles. I remember that some woman almost knocked me down 2 blocks from home on the last lap. I remember eating a dozen or so plums when I finished. And I remember lying on the floor, listening to Steely Dan's "Aja," and the Beatles "Let it Be," so high I might just as well have smoked a joint. And finally, I remember losing a water bottle off a grocery cart later at the store, looking at it lying on the floor, and wondering who lost it. This was the first time I wondered why we do the things we do.
In 2015, the night before the Oregon Gran Fondo, my wife is asking me the same question. I am giving her the same answer. "I don't know."