Find the name of a CCTV documentary. 20 1 1 Tomb-Sweeping Day was released around, and it was a feature film about chengdu-kunming railway.

It's called memory 1970. The film was released last year, which was made to commemorate the 40th anniversary of chengdu-kunming railway. This 40-minute documentary tells a hard and touching story about the construction of chengdu-kunming railway.

The film begins with a floating tunnel on the Jinsha River. According to the historical context, combined with the memories of the road-building process of several old railway soldiers, such as Yang Yixun and Meng Xingshi, a large number of precious video materials of tunnel and bridge construction in that year were called to reproduce the arduousness and arduousness of this railway construction.

Chengdu-kunming railway 1970 opened to traffic. There are many peaks and deep streams along the line, and bridges and tunnels account for nearly 50% of the whole line. It was called the railway built in the tunnel on the bridge by the old railway soldiers who built roads that year.