In the heart of Mackenzie Country, the road from Lake Tekapo to Lake Pukaki curves through Simons Pass, over the remnants of an ancient glacial moraine – a low ridge of rocks carried by a glacier during a previous ice age. It’s here that most visitors to the Mackenzie catch their first glimpse of Aoraki/Mount Cook, gleaming white beyond the tawny tussock landscape and the turquoise waters of the lake.