Colonial Knob is the high ridge west of Porirua, reached by a steep walk through open hill country. The climb is exposed and can be windy, but the reward is a wide view over Porirua Harbour, Cook Strait, and the hills around Wellington.
In winter the upper slopes can be cold and occasionally snowy. On clear days, it is one of the best short hikes near Porirua for getting above the city and seeing how the harbour, suburbs, and coast fit together.