On its way to the sea, a river or stream may plunge over a steep
cliff. If it does, there is a waterfalls in mountains than anywhere
else. Many waterfalls were caused when ancient glaciers of earthquakes
created a sharp-edged cliff in the path of a stream or river.
Often,
waterfalls are caused as the river carves away at the riverbed as it flows
downstream. Over the years, a softer place in the riverbed wears down and
becomes a steep cliff.
Giant waterfalls are called cater acts. Where the water does not
drop straight down, but rushes down steep slopes instead, it is called a
cascades. If a riverbed slopes even less steeply, it is often called a
rapids.
As far as anyone knows, the highest waterfalls in the world is
Angel Falls in Venezuela. It is a silvery ribbon of falling water that
plunges over 3,000 feet down the face of a cliff
