Earth
Why do cliffs crumble into the sea?
Because waves, weather and gravity wear away their edges. Sea waves hit the bottom of a cliff again and again. Rain, cracks and wind weaken the rock above, so pieces eventually break off and fall.
Earth
Because waves, weather and gravity wear away their edges. Sea waves hit the bottom of a cliff again and again. Rain, cracks and wind weaken the rock above, so pieces eventually break off and fall.