Last summer vacation, I went to Lhasa. I went there by train with my mother.

We lived in Chengdu. It was very far from Lhasa. We wanted to go there by plane before. But we heard the scenery was beautiful along the way. ①因此我们选择了乘坐火车。 It would take us two days.

We got to the train station early in the morning. The train didn’t come. We waited for it at the hall. There were a lot of people waiting for the train. Some people talked with each other. Others sat on the chairs.

Fifteen minutes later, the train arrived. Luckily, we had seats near the window. There were many people from different places on the train. Some people were friendly but some were not. A funny boy sat next to me. He talked a lot and had a good time.

After the train started, I looked out of the window. Everything was green. It looked nice. I really enjoyed the beautiful natural scenery along the road.

The trip to Lhasa took much time, but I enjoyed it a lot. ② It was really a different trip for me.

Grass is very useful. It’s the food of the animals, and also a kind of fuel (燃料). What else can we do with it?

A farmer named Rob Marshall makes a castle with grass. He is from Victoria (维多利亚), Australia. He is 40 years old now. He spends six hours building the 30-meter-long and 6-meter-wide castle. The castle is not huge or strong. But it attracts (吸引) many people to visit it. Hundreds of tourists have visited the castle. The farmer welcomes the people. We can visit the special castle or we can make our own (自己的) castle in the future.

All aboard! Let’s take a ride on the world’s highest railway——the Qinghai-Tibet Railway (青藏铁路). Sit back and enjoy the journey. Get ready for the trip of a lifetime.

We’re leaving Qinghai Station. The scenery along the way is some of the wildest in all of China.

Keep your eyes open as we race through this beautiful land. You might see some Tibetan antelopes (藏羚羊) from your window.

Before we begin our journey, let’s learn about this amazing railway. It’s truly one of the great engineering wonders of the 21st century. When people finished building it on July 1st, 2006, the Tibet Railway set nine world records, including the world’s highest railway at 5, 072 metres above sea level, the world’s highest tunnel (隧道) at 4, 905 meters, and the longest tunnel ever built on permafrost (冻土) .

As we travel higher, the air gets thinner and thinner. Soon there will only be 50 to 60 percent of the oxygen which we are used to breathing. But don’t be afraid. Each rail car has two separate   (独立的) oxygen systems (系统). One system spreads oxygen throughout the train at all times. And each passenger can also get a personal oxygen mask just like those used in planes.

Here are a few more things to think about as our train leaves the station. The designers solved three main challenges (挑战) when building this great railway. First, the high altitude (海拔) made the task difficult because there was no enough oxygen. Second, much of the railway runs across permafrost, a type of ground that keeps changing as the weather warms and cools. Finally, the railway goes through some of the most sensitive ecology (敏感的生态环境) in China. Great care was necessary to make sure of the smallest possible influence (影响) on nature.

All three challenges were met, making our trip possible. All aboard! The train to Tibet is leaving in fifteen minutes.