Which of the following activities is least likely to be found near Niagara Cave?

The activity that is least likely to be found near Niagara Cave is ice skating. This is primarily because ice skating typically requires a safe, frozen body of water or an ice rink, conditions that are not commonly present in the vicinity of natural caves like Niagara Cave. The climate and geographical features of the area do not lend themselves to the kind of environment suitable for ice skating most of the year.

In contrast, camping, hiking, and picnicking are much more aligned with the outdoor recreational opportunities that nature reserves and cave parks tend to offer. These activities are popular for visitors looking to enjoy the natural scenery and landscape surrounding the cave, making them more applicable in this context.