Boca do Inferno, or "Mouth of Hell," is a dramatic cliff formation located near Cascais, Portugal. It features a series of caves and blowholes where the Atlantic Ocean crashes against the rocks, creating spectacular waves and sounds. This natural phenomenon is a popular tourist attraction, drawing visitors who want to witness its beauty and power. The site is steeped in local legend, with stories suggesting that it was once a place where demons would emerge. Today, Boca do Inferno is not only a geological wonder but also a scenic spot for photography and enjoying the coastal landscape of Lisbon.