The Circumetnea narrow-gauge railway has circled Europe's most active volcano for almost 120 years, and this film rides the full three-hour route from Catania to Riposto on the Ionian Sea. The track crosses black lava fields that look lunar, threads through prickly pear scrub and wooded nature parks, and passes deserted stations left behind after the rest of Sicily's narrow-gauge network shut down. Eruptions have forced repeated rebuilding of the line, most recently in 1981, and the film explains how a mountain standing 3,352 meters tall keeps damaging and reshaping the very rails built to circle it. Footage tracks the train through more than 100 kilometers of shifting terrain, from wooded hills to bare volcanic rock, with Etna's summit visible for most of the journey. Along the way the film covers the volcano's eruption patterns, from routine crater activity to the rarer violent episodes that send ash and rock kilometers into the sky, grounding the scenery in the geology that produced it.