What aspect of cave tours often surprises visitors?

The stunning beauty and size of the formations is often the aspect that surprises visitors during cave tours. Many people have preconceived notions about caves, expecting them to be dark and unremarkable; however, upon entering a cave, they are often taken aback by the intricate stalactites, stalagmites, and various mineral formations that create breathtaking displays. The sheer scale of these natural formations can also be awe-inspiring, leading to an unexpected appreciation for the geological processes that shaped the cave over thousands or even millions of years.

While the other options touch on aspects of the cave experience, they do not typically generate the same sense of wonder. For instance, while darkness and cold temperatures are common characteristics of caves, they may not evoke a strong reaction compared to the visual impact of formations. The presence of artificial lights serves to illuminate the beauty of the cave but is not typically a surprising factor for visitors, as they anticipate some form of lighting for safety and visibility. Lastly, while some caves may lack visible life forms, others might feature organisms specifically adapted to cave environments, so the surprising element could vary widely depending on the cave being toured. Therefore, the remarkable aesthetic and scale of the formations remain a highlight for most visitors.