Originally the Dublin Bottling Works, the plant was founded in 1891 by Sam Houston Prim, an entrepreneur who some say gave up a potential fortune. In 1922, when franchise opportunities were introduced, Prim was asked to choose his territory. As the story goes, he looked at a map, drew a circle around Dublin 45 miles in radius and said, "This will do for me."

Little did he know that years later, people would be coming from as far as Florida and California just to purchase cases of Dr. Pepper from his plant. Why? Well, the claim to fame here at the Dublin works, aside from being the World's Oldest Bottler of Dr. Pepper, is that it is the only plant where the original Dr. Pepper formula is still in use. You see, they still opt for pure cane sugar over the cheaper, more common corn sweeteners used in most soft drinks today. And if you're addicted to the stuff like I am, you really can tell the difference. In fact, I have a faint suspicion of the old formula's healing properties, as it appeared to cure my sore throat with which I had been battling for a week.

However, the pleasure of a visit to the Dublin plant doesn't end with the taste of old-time heaven. With the purchase of a reasonably priced ticket, you get a first-hand look at the bottling process yourself. And any tour with moving parts gets an A in my gradebook, so there was no chance I was going to pass that up.

I arrived on a Tuesday, which is traditionally bottling day at the plant, and entered through Old Doc's Soda Shop. (Travelers, please note: Bottling day has since been moved to Wednesdays.) The soda shop is a recently renovated room boasting a working soda fountain that serves up delicious sandwiches, ice cream and of course, Dr. Pepper. I, as always, ordered something with turkey and grabbed a couple bottles of Pepper from the fridge in the corner, pausing to teach a fellow tourist how one works a non-twist-off bottle cap.

Quickly polishing off my sandwich in anticipation of the next tour, I perused the sizable display of souvenirs and memorabilia, and had myself yet another bottle of DP. It was then that I began to realize the magic of the Dublin recipe; it seemed I was copping an actual soda buzz. No wonder people come from so far to buy the stuff.

As luck would have it, I and only two others made up the entirety of the next hour's group. Tour guide Alicia assembled us together and commenced her well-rehearsed show and tell — but not before handing us each a complimentary bottle of the Doctor's sweet elixir. (One more and I was going to need a shot of insulin.) This time, however, the intoxicating liquid came in bottles nearly 20 years old. The Dr. Pepper was fresh, of course, but I couldn't help but calculate in my head the number of lips the container had crossed paths with and wonder whether that was a bad thing or a good thing.

Unfortunately, the actual Dr. Pepper syrup is concocted in another part of the plant, where mere visitors are not allowed, lest covert soft-drink spies uncover the secret formula. And it didn't do any good trying to sweet talk Alicia, either. Believe me, I did my best. The only thing she would reveal is that the secret ingredient is not prunes as rumor insists. "Myself, I taste a hint of cherry," I remarked casually. But, Alicia wasn't about to fall for my deceptively simple comment. She would neither confirm nor deny. It was name, rank and serial number only. There would be no hush-hush, knock-off garage operation for me. Not this time around.

Besides, today they were bottling one of their other potions, the very southern Big Red, which we followed through the declassified portion of the bottling process. We were introduced enthusiastically to the very large bottle-washing machine — which does a much more thorough job than the quick rinse of cold water the bottles got in the early days — and were shown the filling and capping process. From there, the bottles' caps are tagged using the industry's state-of-the-art dating system: the Marks-a-Lot on a stick. (Since Dublin's stock doesn't stay in storage long, they use a rotating scheme of four marker colors, changed each month.) Finally, the bottles are manually checked for color using a light box and packed away in old-fashioned wooden crates.

The rest of the tour took us through a museum-quality collection of Dr. Pepper antiques and memorabilia belonging to long-time owner Bill Kloster, who had worked at the plant since age 14 when he was a bottle sorter. Bill Kloster became general manager after World War II and took possession of the plant in 1991 when then-owner Grace Prim Lyon, daughter of Sam Houston Prim, passed away. In total, Mr. Kloster worked at the plant for 67 years and had fondly become known as Mr. Dr. Pepper.

Unfortunately, Bill Kloster was otherwise engaged during my visit and I was unable to meet him — a lost encounter I regret because he passed away less than two years later in 1999. Since then, a bronze statue titled Sweet Inspirations has been erected in front of the plant in his honor.

But, thanks to Mr. Dr. Pepper's commitment to his company and his product, I was able to experience a part of Texas history first-hand. I had to give back the 20-year-old bottle at the end of the tour, but I came away with some fun memories, a working knowledge of soft-drink bottling, and most importantly, a real good caffeinated sugar high.