From the high mountain peaks of the Southern Alps, the snow-fed Rakaia River travels 145 kilometres (90 miles) along the boundary between Selwyn and Ashburton districts before joining the Pacific Ocean just south of Lake Ellesmere near the village of Rakaia Huts.

It is one of the world's best examples of a braided river system, with its many streams and channels of shifting gravel constantly moving to present new challenges and opportunities for rafters, jet-boaters, anglers and, of course, the fish and birds that live there. 

Rakaia is Maori for "walking in ranks", an apparent reference to the way in which old time Maori foot travelers once crossed the river. These days crossing the river is much easier thanks to the twin bridges at the spectacular Rakaia Gorge, where there are also picnic areas, and the long bridge which traverses the river on the main southern highway adjacent to Rakaia township.

The latter is the longest bridge in the South Island and, given the difficulties presented by the mobile shingle riverbed, an impressive feat of engineering.

Like its sister river, the Waimakariri, on Selwyn District's northern border the Rakaia changes from deep fast water in the mountains to shallower braided streams as its wide gravel riverbeds cross the Canterbury Plains. 

Salmon and trout thrive in the Rakaia's fresh, mountain-fed, waters and several unique water birds thrive in its shingle stream beds, including three threatened species: the wrybill plover, the banded dotterel and the black-footed tern. The wrybills breed nowhere else. Although they may winter as far away as Australia, they always come home to lay their eggs and raise a family.

Unsurprisingly, the Rakaia River is popular with rafters, jet-boaters,  canoeists, anglers, trampers, campers and picknickers, many of whom flock upstream to the gorge or downstream to the river mouth, where the village of Rakaia Huts swells with visitors every fine weekend and summer evening.