上刀山，下火海

shàngdāoshān,xiàhuǒhǎi
  1. lit. to climb mountains of swords and enter seas of flames (idiom)
  2. fig. to go through trials and tribulations (often, for a noble cause)

CEDICT

Entry Composition

1 上 shàng
  1. (bound form) up; upper; above; previous
  2. first (of multiple parts)
  3. to climb; to get onto; to go up
  4. to attend (class or university)
  5. (directional complement) up
  6. (noun suffix) on; above
2 刀 dāo
  1. (slang) (loanword) dollar
  2. classifier for sets of one hundred sheets (of paper)
  3. classifier for knife cuts or stabs
  4. (Internet slang) to bargain; to ask for a small discount (esp. on second-hand marketplaces)

classifier: 把
3 山 shān (coll.) small bundle of straw for silkworms to spin cocoons on

classifier: 座
4 下火 xiàhuǒ to ignite; to set on fire
5 海 hǎi
  1. ocean
  2. sea
  3. great number of people or things
  4. (dialect) numerous

classifiers: 個, 片

Related entries

上刀山，下油锅 shàngdāoshān,xiàyóuguō
  1. lit. to climb mountains of swords and enter cauldrons of boiling oil (idiom)
  2. fig. to go through trials and tribulations