Niangziguan is the largest spring of rock dissolved , located in pingding county of shanxi province . it situated in the middle of taihang mountain and in the junction of tao river and wen river 娘子关是我国北方最大的冷水泉，位于山西省平定县，地处太行山中段， 37 20 38 20 n ， 113 114 e ，出露于桃河与温河汇流地段。
