This spectacular, north-northeast-looking, low-oblique photograph shows the high country of the Southern Alps and two glacier-fed lakes, Pukaki and Tekapo. Visible near the northwest corner of the photograph is Mount Cook, the highest peak in the Southern Alps at 12 349 feet (3766 meters). East of Mount Cook is the largest glacier in New Zealand, the Tasman Glacier, 18 miles (29 kilometers) long and more than 1 mile (2 kilometers) wide. The Southern Alps, paralleling the west coast of South Island, are extensively glaciated with many deep gorges. Of the 3155 active glaciers in the Southern Alps, most are within 100 miles (160 kilometers) of Mount Cook. From Tasman Glacier, the braided Tasman River can be seen flowing southward into beautiful Lake Pukaki. The lake is more than 9 miles (15 kilometers) long and covers 32 square miles (83 square kilometers). Its brilliant turquoise color results from finely ground rock flour being suspended in the water. East of the Tasman River, the braided Godley River flows into Lake Tekapo, a beautiful lake occupying a vast hollow in downs and terraces of golden tussock grass. Though a hydroelectric control structure now contains the waters of the lake at its southern end, Lake Tekapo owes its origin to the natural dam of an old moraine. East of Lake Tekapo, the agricultural lands of the fertile Canterbury Plain spread toward the coast.