During eruptions, tunnels may be formed such that lava flow inside remains hot and in molten state whilst the cave’s walls become cold and solidify. As a consequence long (up to 1500 m) caves may be formed. Hundreds of them are found in the etnensis system. One such cave, “Grotta del gelo” (Grotta of ice), at a height of 2000 m preserves ice in its innermost year-round. It is the only “glacier” that can be found in the Mediterranean Sea area. c) The surface of the etnensis cone is pitted with many subsidiary (or temporary) craters, even at low heights. In the center of Catania, the so called “Ascent Sangiuliano” is the slope of an ancient explosive crater (i.e. emitting gas and “lapilli”, not lava). In ancient times, the slopes of Etna were rich of thick forests. At lower heights anthropization has caused many of those forest to be replaced by rich citrus and orange groves, gardens, vineyards. The well known “Nerello Mascalese” is obtained from a vine cultivar native of Etna slopes, Above 1000 m asl a scattered forest zone has developed : at lower levels prevail chestnut, ilex, ashy, at higher level larch, still higher beech and birch; the variety “Betula Aetnensis” may go up to 2300 m asl, a botanic rarity found mainly on east slopes of the volcano. From this height up to 2500 m asl, the volcanic landscape is characterized by scattered “Spino santo” bushes (Astragalus Aetnensis) whose strong radical apparatus fixes vast extensions of the otherwise sterile volcanic summit and start its colonization, giving in addition shelter to smaller and more delicate creatures (such as Senecio Aetnensis,Viola Aetnensis,Rumex Aetnensis,Seleranthus Aetnensis,Saponaria Sicula, determining unique botanic associations). Above 2500 m asl only some minuscule herbaceous species can be found up tp 3050 m asl where, on the west side, between Main Crater and Punta Lucia Anthemis Aetnensis and Senecius Aetnensis may be found . Above 3050 m asl there is only a barren desert, battered by impetuous winds with prevalent W/NW direction, ambient temperatures often falls below freezing point (while the ground may be hot). There, silence is broken only by the wind’s whisthling and by the giant’s dull mumbling that rises from the abyss.