There is an amazing phenomenon on our big planet Earth. These are mountains-volcanoes, the direct gateway to the underworld of the planet. They are always unpredictable. Volcanoes sleep for years and centuries, and then wake up and spew boiling lava from the bowels of the Earth. Clouds of ash rise into the sky, hot lava flows along the slopes, clouds of hot smoke envelop the peaks of the volcano. Whole flashes of fire burst to the surface. Sometimes hot fragments of rocks scatter far around. In Europe, the largest active volcano is Etna in Italy, nicknamed the Fiery Mountain. Just like in the fairy tale "The Lord of the Rings". The mountain is also called "Big Mama". The smoke smoking over its crater reminds that This is not a simple mountain.
