Campi Flegrei, or the Phlegraean Fields, is a large volcanic area located near Naples, Italy. It is known for its calderas, hot springs, and fumaroles, which are openings in the Earth's crust that emit steam and gases. The area is a popular destination for tourists and researchers interested in geology and volcanology. The last major eruption of Campi Flegrei occurred in 1538, forming the Monte Nuovo volcano. Today, the region is closely monitored due to its potential volcanic activity. It is also rich in history, with archaeological sites that reflect the ancient Roman civilization that once thrived in the area.