Write a 200-word article about the track lock of Dadu Bridge.

The lyrics of "Dadu Bridge Crossing Iron Cable Cold" are about Dadu River and Luding Iron Cable Bridge. Now, we can enjoy the rivers and bridges slowly.

Come to the abutment in front of Luding Bridge and see the Dadu River under the bridge. The river is surging. From time to time, big waves rise into the sky, dive down and splash. The momentum is no worse than that of the Yellow River. Looking up, I looked at this lonely iron cable bridge, rickety. This bridge is more than two meters wide, about three meters wide. There are nine ropes in the middle of the bridge with three boards on them. One foot can be put on each board. There are two thick and long iron ropes on both sides of the bridge as handrails and railings. Under the bridge is a swift river. Grandpa led me, and we walked step by step. The bridge is rickety, and walking on it is like swinging. The river below and the red Dadu River hit the rocks, splashing waves several meters high. You got me, Abala. We followed the queue, and the sound of the waves was deafening. My mother walks behind me. "Don't look down." Mom reminded me. I looked up at once. There's an uncle coming ahead. We have to make way. My hands are holding my grandfather tightly, and my feet are moving slowly. I was very nervous and finally walked through this dangerous road.

Looking up, it's almost there. I stepped up and walked to the balcony at the end. Looking back at this 100-meter railway bridge, I think of the Red Army flying over Luding Bridge and this poem-"Long March": The Red Army is not afraid of the expedition, and Qianshan is only idle. Wuling makes waves, and Wumeng takes mud pills. Jinsha River is warm in the clouds and cliffs, and Dadu Bridge is cold with the horizontal rail. ...