在渡口市把关河西岸海拔1300～1600米的石灰岩山地上,科学工作者发现了一片珍贵的天然苏铁林。计有个体六万株,占地面积约十平方公里。苏铁类植物,最早出现在距今两亿多年的古生代二迭纪,中生代晚三迭纪至早白堊纪为繁盛时期。后来由于自然条件的变化而激剧减少,仅有少数种类保存下来,繁衍至今,因此被人们誉为 In the ferry mountainous area where the west coast of Guanhe River shores 1300 ~ 1600 meters above sea level, scientists have discovered a precious natural cycad forest. Total 60,000 individuals, covers an area of ​​about 10 square kilometers. Cycas, first appeared in the Paleozoic over two hundred million years ago, the Mesozoic Late Triassic to Early Cretaceous period. Later, due to changes in natural conditions and dramatic decline, only a few species preserved, multiply so far, it was praised as