The silk fabric is generally thought of as being developed in China around 3000 BC. According to a popular Chinese legend, Lady Hsi Ling Shi was sitting in her garden when a silk cocoon fell into her hot tea which loosened the long strand of silk. The subsequent invention of the loom and the origin of sericulture (the raising of silk works to produce silk cocoons) are also credited to Lady Hsi Ling Shi. For the next two thousand years, the knowledge of how to cultivate silk worms to produce silk fabrics was kept as a nationally guarded secret. There is evidence to suggest that the trading of silk started sometime around 2000 BC and the trade route that spanned from Asia to Greece, Middle East, India and North Africa was called the Silk Road.