On July 9th key control project of the entire Dali-Lin (Cang) railway, the Hongdoushan Tunnel, was successfully breakthrough. Very special difficult tunnelling conditions toxic and harmful gases.

During Dalin Railway Hongdoushan Tunnel is 10,616 meter excavation 8 kinds of poisonous and harmful gases came.

Overcoming problems 4 construction methods used 40 patents used. Trains go 160km speed after tunnel finish.

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