Tulips were first imported from the Ottoman Empire in the 16th century. By 1637, the bulbs became so popular, expensive and speculative that they caused an economic collapse in Holland called Tulip Mania. Today, tourists flock to the country from mid-March through mid-May to behold fields blooming with the national flower. The next best thing is to visit the Amsterdam Floating Flower Market. Bloemenmarkt consists of barges tethered along the Singel canal. Since 1862, the vendors have sold a wide array of flowers, plants, bulbs and seeds plus souvenirs.