Research methods: Some focus issues have been put forward in the design of difficult mountain railways based on the experiences in survey，design and coordinating construction of many railways in southwestern China.
Research Conclusions: In order to improve the design level of railways in difficult mountain area a proper route aternatives should be chosen and the main technical standards should be determined by comparison. The long and deep section of sufficient grade and extension of line should have top-down alignment， avoiding shallow burying tunnel and tunnel group as much as possible. We should identify the geological conditions for large-scale spoil site and avoid man -made geologic hazard.
2007, Vol. 24 
