These people developed within the Mechanical City, accumulating quite a population.
Later, as civilization advanced, many people from outside would come back to visit relatives, among other things.
Many people have special feelings toward the Mechanical City—it's their Holy City, their hometown. After leaving, they longed to return every day.
Especially the elders like Yang Lie, they would stay in the Mechanical City for most of the year.
But starting more than thirty years ago, many people gradually moved away and stopped living in the Mechanical City.
There didn't seem to be any particular reason; they just wanted a change of environment, after all, the three hundred cities outside had far more variety and novelty compared to the unchanging Mechanical City.
After these people moved away, they never returned.
Moreover, as more people moved away, the Mechanical City increasingly felt deserted, almost like a "Ghost City."
