《徐霞客游记·黔游日记一》
这个囤子又圆又大，四面是绝壁，仅在西北方有条山脊通有石阶上囤子，路必定要环绕到下边的峡谷中，所以是天险。
其囤圆而大，四面绝壁，惟西北有脊通级而上，路必环旋于下峡，故为天险。
This stockade is round and large, and the four sides are cliffs. There is only a mountain ridge in the northwest with a stone staircase leading to the stockade. The road must be circled to the canyon below, so it is a natural danger.
<s>[INST] Convert the following English text into Classical Chinese: This stockade is round and large, and the four sides are cliffs. There is only a mountain ridge in the northwest with a stone staircase leading to the stockade. The road must be circled to the canyon below, so it is a natural danger. [/INST] 其囤圆而大，四面绝壁，惟西北有脊通级而上，路必环旋于下峡，故为天险。</s>
Convert the following English text into Classical Chinese: This stockade is round and large, and the four sides are cliffs. There is only a mountain ridge in the northwest with a stone staircase leading to the stockade. The road must be circled to the canyon below, so it is a natural danger.
user
其囤圆而大，四面绝壁，惟西北有脊通级而上，路必环旋于下峡，故为天险。
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