To the Fiordland

The serene deep waters of Lake Te Anau make up the largest lake in the South Island. Gouged out by a huge glacier, it has three arms, is 352 sq km in area, 64km long and its deepest point is 417km. The township is beautifully situated beside the lake, and acts mainly as a base for visitors traveling to Milford Sound.

Te Anau Lake

The hotel where we stayed, right across the lake

A major highlight of Te Anau is the Glowworm Caves, part of a 6.7km, four-level limestone labyrinth known as the Aurora Caves system. The caves are about 12,000 years old, but the limestone they carve through is ancient – up to 35 million years old. The caves are still increasing in size, as the river that flows through the caves is midly acidic, which helps to dissolve the rock and create passages. The caves were rediscovered in 1948 by local tour operator Lawson Burrows. Intrigued by the Maori tales of Te Anau au (cave with a current of swirling water) from which the lake takes its name, Burrows spent three years searching for the spring. When he found a stream gushing out of the hills along the edge of Lake Te Anau, he squeezed through the rocky entrance and surfaced in a dark cave. Above his head, he was stunned to see thousands of glittering glowworms.

Glowworms fish for food by dangling as many as 70 ‘fishing lines’ which are 20 – 150 mm long and covered with thick sticky droplets of mucus. The ‘fishing lines’ are really pretty, looking like strings of diamonds. The brilliant lights of the glowworm attract flying insects which then become trapped and paralysed by chemicals in the lines. When the glowworm feels vibrations on a line, it quickly hauls in its victims, kills it and sucks its juices. Gross eh? The hungrier the worms, the more brightly they glow. Glowworms only feed during their larval phase. As an adult, it has no mouth.

We signed up for a trip to the Glowworm Caves, and the excursion began with a scenic cruise across Lake Te Anau on board the catamaran Luminosa to its western shores. On disembarking, we went underground to view the dynamic environment of the caves in which water action steadily erodes the fractured limestone. It is a mysterious world of rock formations and fossils, waterfalls, whirlpools and a cavern with rock walls towering high above. Beyond these is the magical glowworm grotto. The delicate incandescence of thousands of glowworms is an entrancing and unforgettable sight, like a clear summer sky decorated by millions of stars shining brightly. Photography is not permitted inside the caves as the worms react to light and noise by switching off.

The Luminosa leaving a trail of water behind

The sun setting down outside the Glowworm Caves