Take the Chicago Board of Trade, add a little New York Stock Exchange, cover it all with more flowers than you'll find in the Tournament of Roses Parade, and you have Aalsmeer, Amsterdam's Wall Street of Flowers.

Remember what red roses cost on Valentine's Day?

The market price was likely set in three seconds by a bleary-eyed, coffee-swilling, stressed-out buyer bidding in the world's largest flower auction at Aalsmeer, a small Dutch town near Amsterdam. The system originated 100 years ago with "green auctions," where buyers would gather in a farmer's field to bid on vegetables. Aalsmeer's flower growers adopted the idea, formed a cooperative, and in 1911 held the first auction, in a coffeehouse.

Today, that cooperative has more than 3,000 members, and the coffeehouse has been replaced by a sprawling, 350-acre complex, where 2.1 million cut flowers and plants - $21 billion worth per year - come in every weekday, go on the block, and move on. No wonder the auction building itself is one million square meters - that's 250 acres or 165 soccer fields - making it the world's largest commercial edifice, according to the Guinness Book of World Records. Workers whiz around on bicycles because distances are too far to walk.

Open round-the-clock on weekdays, Aalsmeer Flower Auction is a self-­contained world of color, fragrance, and frantic activity.The main building houses five auction rooms, a dispatch and loading center, forwarders, customs and plant protection services, banks, and restaurants. Flowers and plants arrive in the middle of the night, trucked in from Dutch greenhouses or own to nearby Schiphol Airport from nurseries in Kenya, Israel, Ecuador, Spain, and elsewhere. Exporters and wholesalers are in their offices by 5 a.m.to prepare for the day's buying.

Officially known as the Bloemenveiling Aalsmeer (VBA), the auctions themselves start at 6:30 a.m. By 7:30 a.m., visitors are admitted for a self-guided tour that runs a half-mile through the main operations of the massive building and allows a peek at four of the five auction rooms.

From a catwalk suspended 20 feet above the climate-controlled distribution hall, visitors look down on thousands of three-tiered trolley carts packed with 12,000 varieties of cut flowers and potted plants. The carts, each the size of a Sub-Zero freezer, are stacked with buckets of roses, tulips, hyacinths, lilacs, orchids, hostas, hydrangeas, chrysanthemums ... It's an ocean of flowers.Red roses predominate, as they are top sellers worldwide. But even with those, tastes vary: Some countries prefer long stems, others want large-headed roses that make a statement with a few stems. Roses and tulips are the most popular flowers exported to the U.S., which along with Japan accounts for 10 percent of Aalsmeer's business.