Few things are uniquely born in America. There's jazz music, of course. The Fourth of July. And - finally - there's bourbon.

The amber liquid calls Kentucky its home, and a half-dozen or so distilleries in the state proudly open their doors to visitors year-round for intoxicating tours and programs.

Any bourbon tour would likely begin first with Maker's Mark, which has been producing its bourbon whiskey (they spell it "whisky" in honor of the company's Scottish roots) since 1840.

Quick Shots on Kentucky Bourbon Bourbon is barreled as a clear liquid, like vodka, and changes color during the aging process inside the charred oak barrels. To legally be called bourbon, it must age at least two years. One bluegrass story attributes the process of charring the interior of the barrel to Rev. Elijah Craig, an 18th-century Baptist minister and distiller from Georgetown, Kentucky. Craig "discovered" the process when several barrels he was using caught fire. He went ahead and used the charred barrels, and by the time the whiskey aged, it had turned a golden amber and taken on its unique taste. In 1964, the United States Congress declared bourbon the "official native spirit" of the country. Tennessee whiskey is not considered a bourbon. The Mint Julep, a concoction of bourbon, sugar and mint on crushed ice, is a traditional Kentucky Derby favorite. (Maker's Mark bottles a mint-flavored bourbon around Derby Day; you'll know it by the green wax seal, as opposed to the standard red.) When the United States Navy christened the U.S.S. Kentucky nuclear sub, it employed Kentucky bourbon (a politically correct blend of all the state's brands) instead of champagne. The ABCs of Bourbon What makes bourbon uniquely bourbon? Dave Pickerell, master distiller for Maker's Mark, breaks it down into the ABCs: A. American-made is a must, preferably in Kentucky. B. Barrels have to be brand-new charred oak barrels. C. Corn ratio. You have to use at least 51 percent, plus you have to use a small amount of rye, barley or wheat flavoring grain as well as yeast. Pickerell adds that certain temperatures must be strictly observed in the fermenting process, it must be bottled at a minimum of 80 proof, and no added alcohol or artificial colors can be involved. Aging is a factor, too, a minimum of two years. "If you do all these wonderful things, you can call it bourbon."

"This distillery is in the Guinness Book of World Records as the oldest operating bourbon distillery," notes Dave Pickerell, master distiller and vice president for production (as well as a Dayton, Ohio, native). Maker's Mark also lays claim to being the first distillery named a National Historic Landmark, back in 1980. (All this said, other distilleries also lay claims to being a "first.")

"Of all the distilleries, this is the most complete," claims Pickerell. "You get to see the mashing and everything. At the end of the tour, visitors get the opportunity to buy a bottle and hand-dip it themselves in our signature red wax. Except, of course, on Sundays.

"It's a great visit," adds Pickerell. "Our objective is to spoil our visitors. It is such a wonderful setting, a marriage of heritage and craft."

More than 90 percent of the country's bourbon is produced at distilleries in central Kentucky, amid the rolling bluegrass landscape and thoroughbred horse farms. Call it wine country without the wine.

Though technically bourbon can be produced anywhere, Kentucky is the only state allowed to place its name on the bottle. Originally shipped through Bourbon County, barrels were stamped with the county's name and soon this Kentucky whiskey became known as bourbon.

Many distilleries are located in or around Bardstown, Kentucky, called the "Bourbon Capital of the World" — in part because the area's water supply boasts very high limestone content and low iron, somehow making it a perfect ingredient to distill bourbon. Each September, the annual Kentucky Bourbon Festival in Bardstown is a five-day event that attracts tens of thousands.

Thanks to its distinctive aroma, any distillery tour is a treat for the senses, full of aromatic copper and steel tanks, vanilla scents and caramel bouquets. Be forewarned: Most tours involve walking and stair-climbing, so make sure to wear comfortable shoes.

Maker's Mark

The distillery is located on scenic 850-acre grounds framed by magnolias and sugar maples. On display: an antique fire engine in the fire department, the original owner's Victorian house, a road toll house, a quart house (believed to be the nation's oldest remaining retail whiskey store), barrel warehouse, still house and Visitors Center. In the gift gallery, you can buy a small bottle (if you're 21 or older) and plunk it in the "dipping booth," creating a customized red wax sealed bottle that you can sign and date.

The history: Robert Samuels brewed his first batch in 1780 for personal use. Samuels' grandson, T.W., erected the family's first commercial distillery on the family farm in 1840. The name Maker's Mark comes from the tradition of fine English pewter; makers only put their mark on their finest pieces.

Located at 3350 Burks Spring Rd. in Loretto, Kentucky. Tours conducted Mon.-Sat. hourly on the half hour,

10:30 a.m.-3:30 p.m. Sunday tours conducted March-December only at 1:30, 2:30 and 3:30 p.m. (No liquor sales on Sunday.) Free. Contact: 270/865-2099 or www.makersmark.com.

Jim Beam's American Outpost

The Visitors Center offers an abbreviated look at the bourbon-making process through exhibits that trace the 200-year history of the distilling family. All tours are self-guided. Free tastings are offered in a stately mansion once occupied by Jim Beam's son. On display: the world's smallest working still and an antique version dating to the Revolutionary War era.

The history: Farmer Jacob Beam and his son David Beam began to hit their stride selling bourbon in the early 1800s. During Prohibition, the Beam family was forced to take up growing citrus fruit in Florida, but returned to the bourbon business when Congress declared the booze could flow again.

Located at Ky. Hwy. 245 in Clermont, Kentucky. Open Mon.-Sat. 9 a.m.-4:30 p.m., Sun. 12:30-4 p.m. (no tastings on Sundays). Free. Contact: 502/543-9877 or www.jimbeam.com.

Woodford Reserve

Brown-Forman (owners of Jack Daniel's in Tennessee) re-opened this 19th-century distillery a decade ago; the $14 million complex is a National Historic Landmark. The Visitors Center offers an introductory film, plus exhibits, photos and artifacts about the history of Kentucky bourbon. There's a restaurant and gift shop that features wine racks made from whiskey barrels, among other bourbon-inspired fare. The 78-acre site includes all aspects of bourbon production. Begin your tour with a stroll through the facility where the sour mash bubbles in unique cypress

fermenting tanks. On display: The distilling room, dating to 1840, features copper pot stills just like ones used a century ago. Other exhibits reflect on the art of coopering the barrels, as well as a walk through the only surviving stone aging warehouse in America. The tour ends with samples of bourbon balls.

The history: Elijah Pepper birthed his golden brown elixir here in 1812. Later, French wine merchant Leopold Labrot and Frankfort, Kentucky, banker James Graham formed Labrot & Graham on the site. Today, Brown-Forman Corp. owns the distillery.

Located at 7855 McCracken Pike in Versailles, Kentucky. Open Tues.-Sat. 9 a.m.-5 p.m., Sun. 12:30-4:30 p.m. Tours conducted hourly Tues.-Sat. 10 a.m.-3 p.m.; Sunday tours conducted April-October only, at 1, 2 and 3 p.m. Admission $5 (includes a tasting and souvenir shot glass), for 18 years old and up. Children free (but no tasting). Contact: 859/879-1812 or www.woodfordreserve.com.

Wild Turkey Distillery

Begin with the Visitors Center, located in a former worker's house, then take one of the four one-hour distillery tours offered on weekdays only. In the summer months, the tour might not include the fermentation room (Wild Turkey shuts down production in the hottest months of the year). On display: various artifacts related to the company's history, as well as segments on the distilling process.

The history: The alcohol is named for the wild turkey hunts favored by the owner and his friends.

Located at 1525 Tyrone Rd. in Lawenceburg, Kentucky. Open Mon.-Fri. for tours at 9 a.m., 10:30 a.m., 12:30 p.m. and 2 p.m. Free. Wild Turkey sold by the bottle, but no tastings. Contact: 502/839-2182 or www.wildturkeybourbon.com.

Heaven Hill Distilleries

The Bourbon Heritage Center denotes the history of the distillery's flagship bourbon, Evan Williams. On display: You can watch the film "Portrait of Heaven Hill," experience interactive exhibits, visit a working rickhouse (the facility where the barreled bourbon is aged) and enjoy a free "Taste of Heaven" in the barrel-shaped tasting room. There's a gift shop on site as well, with copper and oak crafts. You can also purchase a frontier jug of Evans Williams Master Select Bourbon, personalized with your name. The Heaven Hill Trolley can shuttle you through a tour of Old Bardstown.

The history: Founder Evan Williams was known for his hospitality, toting a jug of whiskey to town meetings where he was an early government trustee. Later, members of the Jim Beam family, including Jim's brother Park, would practice their craft here.

Located at 1311 Gilkey Run Rd. in Bardstown, Kentucky. Open Tues.-Sat. 10 a.m.-5 p.m. (last hourly tour begins at 4 p.m.), Sun. noon-4 p.m. (last tour begins at 3 p.m.; no bourbon tastings or sales on Sundays). Free. Contact: 502/337-1000 or www.bourbonheritagecenter.com.

Four Roses

The new Visitors Center is constructed to reflect the distillery's 19th-century Spanish mission style. On display: Interactive exhibits and a 15-minute film detail the craft involved in the bourbon process. A gift shop sells Four Roses brands, accessories and clothing.

The history: Founder Paul Jones Jr. named the bourbon after the corsage of four red roses that played a key role in his courtship of a Southern belle.

Located at 1224 Bonds Mill Rd. in Lawrenceburg, Kentucky. Open Mon.-Fri. 9:30 a.m.-4:30 p.m. (tours given on the hour 10 a.m.-3 p.m.). Free. Contact: 502/839-3436 or www.fourroses.us.

Buffalo Trace

On display: "Hard hat" tours of the production plant are offered by prior arrangement. There's also a museum and gift shop.

The history: This is one of the few distilleries allowed to stay open during Prohibition, producing bourbon for "medicinal purposes."

Located at 1001 Wilkinson Blvd. in Frankfort, Kentucky. Tours on the hour Mon.-Fri. 9 a.m.-3 p.m., Sat. 10 a.m.-2 p.m. Free. Contact: 502/223-7641 or www.buffalotrace.com.