在中国众多的山水美景中,序数自然景观别具风采,这些序数自然景观是:一线天在安徽黄山南部,为登玉屏峰峰顶的要道。两峰之间,狭长如巷,最窄只能容纳一个人通过,仰望高空,蓝天仅露一线。二酉洞在四川酉阳南翠屏山麓。洞深狭长,洞内宛若厅堂。洞壁钟乳溶岩鳞次栉比,千姿百态。三 In China’s numerous scenic landscapes, the ordinal natural landscape has a unique style. These ordinal natural landscapes are: The first line of the sky is in the south of Huangshan Mountain in Anhui Province, which is the main road to the peak of Dengyuping Peak. Between the two peaks, narrow and long as a lane, the narrowest can only accommodate one person through, looking up at the sky, the blue sky is only exposed. The second cave is in the South Tsui Ping Shan, Fuyang, Sichuan. The hole is long and narrow, and the hall is like a hall. Cave wall clock lava rock scales, different situation. three