When a volcano is no longer erupting, some reminders of its explosive force remain. What are the visible phenomena in the countryside which signify a volcano's existence?

The volcano's crater: hardened funnels of extinct volcanoes. These kinds of extinct volcanoes can be found in the 'Seven Hills' region along the Rhine in Germany, and in the high country of the Auvergne, in France.

Lava soil: the substances left by a volcano can be very fertile. In Italy and Japan, it is used for agriculture.


Crater Lake: the summit of a volcano has been thrown out by the explosion and the resultant hole has filled with water. They can be found in Eifel in West Germany.

Mineral Springs: gas mixes with water, putting the water under pressure in the ground. The mineral water is then purified, bottled and sold. Water such as the comes from the Spa Vichy and Ems.


Gas springs: sometimes gas escapes from the Earth, often in caves. The 'Dogs Cave', near Naples, is famous for its toxic gas which remains close to the ground.

Volcanic crevasses: a bubbling, liquid substance, molten basalt, erupts from issures in the earth.