英语听力：自然百科 探索世界奥秘之万里长城 Unit7（在线收听）

探索世界奥秘之万里长城 Unit7

And many never returned home, ending up in graveyards like this one. Large tombs for generals, small ones for the soldiers, and all of them died defending the Great Wall.

But the soldiers' misery did benefit someone. Their presence provided safety from attacks to traders and travelers. Hugging the wall for protection from bandits, caravans left China laden with silk, furs, pottery and rhubarb(大黄), a plant unknown in the West and highly prized as a medicine. This was the famed Silk Road.

The traders returned with gold, ivory and coral. It was a dangerous route, running through some of the world's worst deserts, but at least the wall and its guards stopped raids by nomadic bandits along much of its length. And it wasn't just trade goods that flowed up and down the Silk Road, Along with the commodities came ideas and inventions: from China came the magnetic compass, an invention that made it possible for Columbus to find America, and from the West came religion, early forms of Christianity and most important for the Chinese, Buddhism.

The art that came with Buddhism revolutionized China. Accustomed to building on a massive scale, the Chinese applied what they had learned from building the wall to the new religious art, and the result was colossal.

These giant carved stone Buddhas are among the largest sculptures ever created, a mixture of native artistic talent and foreign ideas. But the art wasn't always on such a grand scale.

The little desert oasis of Dunhuang(敦煌) is where the travelers on the Silk Road sheltered by the Great Wall rested and prepared for one of the toughest stretches of their journey.

Soon they passed through the Jade Gate(玉门关), the last gateway in the Great Wall and headed for the terrors of the Taklamakan Desert(塔克拉玛干沙漠), the worst desert in the world.

To help ensure their safe journey, travelers paid local artists to paint Buddhist shrines in the cliffs around Dunhuang. Shrines in which they had their own portraits painted, a reminder to the gods of their help they would require in the next few weeks.