Answer: crevasses

AnswerCrossword Clue
CREVASSESClimbers' obstacles
CREVASSESPerils for polar explorers
CREVASSESChasms
CREVASSESRange features
CREVASSESLevee breaches
crevassesA deep open crack, esp. one in a glacier
crevassesA breach in the embankment of a river or canal