The Tunnels of Moose Jaw, Saskatchewan.

It is widely documented that, after completion of the CP Railway, Chinese railway workers chosen to live in the cramped, unsanitary conditions of tunnels under downtown Moose Jaw in order to avoid paying the Chinese Head Tax.

According to Moose Jaw: people, places, history – By John Larson, Maurice Richard Libby:

In the spring of 1883, a group of Chinese-hating whites attacked the makeshift British Columbia Camp where hundreds of Chinese workers slept peacefully. They burned the camp to the ground and beat the workers with axe handles. Four men died, three of them because white doctors refused to treat the injured Chinese.

When the railway was completed in 1885, the growth of anti-Chinese sentiment throughout British Columbia had grown so great that many workers began to drift eastward. Many Chinese sought new opportunities in fledgling prairie towns like Moose Jaw. 

If some Chinese men did make use of the tunnels, they were most likely motivated by the simple desire to avoid public persecution, to remain out of sight, and to dispel fears that the Chinese population would adversely affect the local economy.

Chinese Tunnels - Saskatchewan, Canada - Video by Canadian Tourism