Why is China digging the Earth?

I've been hearing rumors lately about China digging the Earth, and I'm really curious about it. Could you explain to me why China is engaging in this seemingly unprecedented excavation project? I'm trying to wrap my mind around the motivations and potential benefits behind such a massive undertaking. Is it related to mining resources? Or perhaps they're searching for something of scientific or strategic importance? Could this be linked to their advancements in technology or a new initiative in the realm of finance? I'm genuinely intrigued and would love to hear your insights on this matter.