旧函谷关、新函谷关和潼关，是崤函古道上先后兴替的三座雄关。

The Old and New Hangu Passes and Tongguan Pass used to be the three impregnable passes along the ancient Xiaohan Road.

老子在西出函谷关时，被边防人员拦住，写下了《道德经》后才被放行。

Laozi was stopped by frontier guards when leaving Hangu Pass for the west, let go after writing down Tao te Ching.

文章以郑西铁路客运专线函谷关隧道横洞挑顶为例，介绍了一种新型挑顶施工工艺——垂直挑顶法。

Taking the cross cave propping in Hanguguan Tunnel of passengers special line on Zhengxi railway, this paper introduces a new construction technique of propping - vertical propping method.