A place where water naturally seeps or gushes from the ground.

A spring coming from limestone rocks.

A spring coming from soil.

A hot volcanic spring.

Springs are fed by groundwater. Springs occur in aquifers, and often occur where a river cuts down to the water table. Other springs occur where a permeable rock is underlain by an impermeable rock. This sometimes gives rise to 'weeping cliffs' as water seeps from the base of the permeable rock.

Springs are not especially common. Most rivers begin with muddy patches on a hillside rather than a bubbling spring. Bubbling springs are only possible where the rock below is permeable, such as chalk or sandstone.