The western flank of the volcanic complex has been the site of several landslides.

However, it is the deep extension of a vastly eroded ancient volcanic complex, which was probably active about 125 million years ago.

Taranaki sits upon the remains of three older volcanic complexes which lie to the northwest.

The summit of the volcanic complex collapsed during at least three major explosive eruptions, about 16,000, 4000, and 300 years ago.

In two areas on the southern side of the volcanic complex, fumaroles can be observed.

No eruptive history ever recorded from this volcanic complex.

The volcanic complex was named by the nearby Alligator Lake.

The location of the volcanic complex is isolated that needs several journeys on foot from the nearest village to reach the mountain.

Due to its remoteness, the volcanic complex is infrequently visited.

The volcanic complex covers 11 x 6 km wide area.