What Are the Chinese Building Underground in Hainan? A satellite captures an image that uncovers the entrance to an underground complex. What is being built there? Facebook Prev Article Next Article Engineering Checkout these cool gadgets... Related Posts The largest jet engine firing up Can Underwater Turbines Solve Our Energy Problems? Africa’s Clean Energy Potential Engineering Mega Pumpkin Launchers Experimental tokamak thermonuclear fusion reactor How Gravity Built the World’s Fastest Jet Suit
