The second episode is interwoven with a Uygur poet's journey to the place his grandfather was born and raised in the southern part of Xinjiang. And it features the No 7556, an Urumqi-Kashgar train, which covers China's longest "green-skinned" train route.

The entire distance is nearly 1,600 kilometers but it costs less than 80 yuan for a seat ticket.

In the third episode the focus is a steam-engine train in southern Sichuan, among the last few of this kind in the world.

And in the fourth, the makers of the series follow an art teacher on the Qiqihar-Heihe train in search of endangered red-crowned cranes and the ethnic Oroqen hunters in northeastern China.

As for the fifth episode, it features a diehard fan of renowned writer Shen Congwen on the Sichuan-Chongqing train who is exploring the mountainous town of Chadong, which inspired Shen's 1934 classic novel Border Town.

Finally, in the sixth episode, a music teacher and a PhD student trace the roots of a Jiangzhou Drum performance, an art form that dates back to around 1,400 years.

Speaking about the series, Ren says: "We hope the documentary will remind audiences of how wonderful life could be if you slow down the pace."