As a kid, I must admit being disappointed that the grass wasn't bright blue in Kentucky bluegrass country, although it does have a bluish cast. Legend has it that this species of grass is the best for raising Thoroughbred racehorses. It must have some effect, because more than two-thirds of the winners of the Kentucky Derby -- America's premier horse race -- have been bred right here on Kentucky's splendid horse farms.
Louisville's Churchill Downs racetrack, its huge white-frame grandstand topped by a distinctive pair of slim gray spires, opened in 1875, and the Kentucky Derby -- originally patterned after England's Epsom Derby -- has been run every May since then. It's the first in the Triple Crown, a trio of renowned flat races for 3-year-olds, and its traditions have become famous, from the prerace singing of "My Old Kentucky Home" down to the garland of 554 red roses draped over the winning colt's neck. Grandstand seats for the Derby must be booked months ahead and cost a fortune; a more casual option is to join the euphoric crowd picnicking in the 40-acre infield (you won't see much of the race, but you'll experience a good party). The Kentucky Derby Museum, open year-round just outside Gate #1 (tel. 502/637-7097; www.derbymuseum.org), has videos and hands-on exhibits (don't miss the one where you sit on a saddle in a real starting gate).
Before you hit the track, though, I suggest driving around the countryside near Lexington, 100 miles southeast of Louisville, to see where generations of Thoroughbred champions have been bred. The most famous horse farm, Calumet Farm, doesn't allow visitors, though you can do a drive-by with Horse Farm Tours (tel. 800/976-1034 or 859/268-2906; www.horsefarmtours.com), which then visits other working horse farms. You can tour Claiborne Farm, Winchester Road, Paris (tel. 859/233-4252; www.claibornefarm.com), where Seabiscuit was born and Secretariat was a longtime stud stallion (his grave is on the farm), or Three Chimneys Farm, Old Frankfort Pike, Versailles (tel. 859/873-7053; www.threechimneys.com), where Seattle Slew was the resident stud. The Kentucky Horse Park, 4089 Iron Works Pike, Lexington (tel. 800/678-8813 or 859/233-4303; www.kyhorsepark.com), has Man o' War's grave and a museum on horse history, but the real fun for kids is walking through the barns, seeing shows in the equestrian arena (April to Oct), and taking horse and pony rides.
Nearest Airport: Louisville International.
Where to Stay: $$$ Seelbach Hilton, 500 Fourth St., Louisville (tel. 800/333-3399 or 502/585-3200; www.seelbachhilton.com). $$ DoubleTree Suites by Hilton, 2601 Richmond Rd., Lexington (tel. 800/222-TREE  or 859/268-0060; www.doubletree.com).