The stars shift, the Dipper turns; seas turn to fields of mulberry.
No one knows how many years have passed.
The lofty city walls are now covered in thick moss.
On some stretches the wall has already begun to flake off in large chunks, some places have even caved in.
The sea is deep blue, yet the submarines humans built still haven't broken through that Great Wall.
The safety base has long since been abolished.
The world has once again split into several countries.
After several world wars, peace finally returned again; restart then develop, develop then restart.
Humankind started from zero all over again and began to develop technology.
In the long river of human history, no one knows how many times this has already happened.
With every round of redevelopment, they never managed to break through this enclosing wall, nor did they ever reinvent the gear that could tread upon the moon.
