火海刀山

Pinyin: huǒ hǎi dāo shān Explanation: 比喻极其危险和困难的地方。 Source: 京剧《智取威虎山》第五场愿红旗五洲四海齐招展, 哪怕是火海刀山也扑上前。” Example: ～无所惧，艰难困苦炼英雄。 Thesaurus:  Trees ordered by the sword, seas of fire and a forest of knifes-an extremely dangerous place which is most difficult to get through, Sword Tree Cutter Mountain, bluff, Cliff Juebi