请翻译以下内容。 China’s first train from Beijing to Tibet set out July 2,2006, carrying business travelers and thrill-seekers on the world’s highest railway. The $ 4.2 billion railway, an engineering marvel that crosses mountain passes up to 16,500 feet high, is part of government efforts to develop China’s poor west and bind poor ethnic areas to the booming east. The mood was festive aboard the train from Beijing on the 48-hour, 2,500-mile journey to Lhasa. “I feel very proud,” said Guo Chaoying, a 40-year-old civil servant from Beijing who said he was going to Lhasa on business. “We Chinese built this rail line ourselves, and it’s a world first, the highest. It shows our ability in high technology.” The specially designed train cars are equipped with double-paned windows to protect against high-altitude ultraviolet radiation. There are outlets for oxygen masks besides every seat, for passengers who need help coping with the thin air. Guo was riding in the lowest-price car, which had only thinly padded seats and no bunks, but he said he didn’t worry about resting. “I’m too excited anyway,” he said,”There’s going to be too much to see.”