KASHGAR, CHINA
Sandwiched between the Pamir Mountains and the Taklimakan Desert, Kashgar's Sunday Bazaar was—and still is—arguably the best market on the Silk Road. Marco Polo is believed to have refueled here. Just as they have for 700 years, vendors flock from the countryside to trade knives, carpets, horses, and saddles. Coveted Item: Handwoven wool and silk carpets from all points along the Silk Road. Haggle Factor: Medium—Uighurs are skilled negotiators, but unsullied by tourists.

CHICHICASTENANGO, GUATEMALA
Every Thursday and Sunday, high in Guatemala's Cuchumatanes Mountains, Maya villagers flock to Chichicastenango, 68 miles northwest of Antigua, to stage the Western Hemisphere's greatest indigenous market. Riotous colors and the aroma of warm tortillas mingle with the scent of sacred copal incense. Coveted Item: A hand-embroidered huipil, a poncholike garment worn by Maya women, $75–$250. Haggle Factor: Medium—you could bargain hard, but don't. Huipiles represent about three months of finger-gnarling handiwork.

FEZ, MOROCCO
Fez's market in the old medina is a treasure hunter's labyrinth enclosed by a medieval wall. Entire sections specialize in leather goods, carpets, intricate brasswork, silver, and the world's finest hashish. Coveted Item: Ornate glass-and-brass hookah with his-and-hers mouthpieces, $30. Haggle Factor: High—divide the asking price by ten, and don't budge until the merchant sells or shoos you away with a grunt. When he calls you back, begin your negotiations in earnest.

PARIS, FRANCE
The adage "one man's trash is another man's treasure" is especially true every Saturday through Monday in Paris. The city's Marché aux Puces de Saint-Ouen, which covers more than 17 acres and has over 2,000 stalls, is the world's largest antique flea market. Coveted Item: Retro fashion—some of it off the rack from design houses. Haggle Factor: Low—with all the European tourists, it's hard to drive a hard bargain here.