China also has more than 3,000 miles of underground tunnels

http://www.businessinsider.com/chinas-df-3a-mirv-multiple-us-targets-one-missle-2012-12#ixzz2FKYExaGs

US Department of Defense

Inverted map, the DF-31A's range is within the penultimate ring and the US between that and the green ring
The DF-31A is portable and launches from the back of a tank, train, or truck. China also has more than 3,000 miles of underground tunnels and highly reinforced military bunkers where it can stash the highly mobile ordnance

Read more: http://www.businessinsider.com/chinas-df-3a-mirv-multiple-us-targets-one-missle-2012-12#ixzz2FeJ2bnom