The Kepler Track is a 60 km (37 mi) circular hiking track which travels through the landscape of the South Island of New Zealand and is situated near the town of Te Anau. The track passes through many landscapes of the Fiordland National Park such as rocky mountain ridges, tall mossy forests, lake shores, deep gorges, rare wetlands and rivers. Like the mountains it traverses, the track is named after Johannes Kepler. The track is one of the New Zealand Great Walks and is administered by the Department of Conservation (DOC).

Compared with other tracks in New Zealand, this walking track is constructed to a very high standard. Most streams are bridged, boardwalks cover boggy areas and the very steep sections have steps. It is a moderate walking track that takes three to four days to complete.

The Kepler Track is also home to the Kepler Challenge, an annual running race that traverses the whole 60 kilometres (37 mi), which the winners complete in less than five hours.

Māori legend has it that Rākaihautū, the legendary leader of the Māori migration canoe Uruao, is said to have named the great lakes while exploring the interior of the South Island. During a period of wet weather, his party found a large and beautiful lake which they named Te Ana Au, meaning cave of rain,^[5] and just south of it another lake which Rākaihautū named Roto Ua, the lake where rain is constant. Today we know Roto Ua as Lake Manapouri. The Kepler is situated between the two lakes.

Richard Henry, Fiordland's first ranger, lived at the southern end of Lake Te Anau for many years and often explored the Kepler area. Surveyor James McKerrow named the range after the 17th century German astronomer Johannes Kepler.^[6]

Early tracks up onto Mt. Luxmore were cut by Jack Beer to provide summer grazing for his sheep.^[7] Many tracks in New Zealand have evolved from Māori trails or pioneer exploration routes.

The idea for the track was first proposed by Alf Excell and Les Henderson. In 1984 in preparation for the National Parks Centennial in 1988, the National Parks Authority (now Department of Conversation) asked all New Zealand National Parks Boards to propose suitable projects to celebrate the Centennial. Project funds would come from the New Zealand Tourist and Publicity Department.

Alf Excell and Les Henderson, two members of the Fiordland National Park Board, came up with the idea of a track they called the “Around the Mountain Walk”.^[8] The track would join two existing tracks, going from Te Anau Lake control structure joining with the track to the Luxmore Mountain Meadows and skirt northern face of Luxmore and take a zig-zag down to the Iris Burn Valley.  It would then travel down the Iris Burn Valley to Lake Manapouri and join with the track from Shallow Bay to Rainbow Reach Bridge and a new track from the bridge along the western side of the Upper Waiau back to the Te Anau Control Structure.

The project was accepted and the Kepler track, however, was established in 1988 and opened in February of that year as a Great Walk as part of the Fiordland National Park Centennial celebrations. It was designed to ease the strain on the popular Milford and Routeburn Tracks.^[2][4] The track had a considerable contribution from the International Expedition Operation Raleigh during 1986/87 when expeditions from around the world constructed much of the walkways and the Iris Burn and Mount Luxmore huts. The caves at Mt Luxmore were also mapped and Mount Raleigh was named above the Iris Burn.

The track is usually recommended to be walked in this route from the Lake Te Anau Control Gates. It can be walked in either direction. If time is short, the track can be shortened to three days by exiting or entering at the Rainbow Reach swing bridge using a car or bus.

While it is possible to complete the Kepler whilst camping this requires a 10-hour hike between Brod Bay and Iris Burn campsites. A much easier option is to stay at Luxmore Hut on the first night, then continue on to Iris Burn campsite for the second night, completing the track to Rainbow Reach on day three. New Zealand Mountain Safety Council's video on the Kepler Track

The price and availability of accommodation varies considerably between the peak season (summer) and the off-season (winter).

The Lake Te Anau Control Gates are approximately 4.6 kilometres (2.9 mi)^[2] from the DOC visitors centre in Te Anau.

The Kepler Track is located in the south west of the South Island. The nearest townships of Te Anau (4.6 km or 2.9 mi^[2] away) and Manapouri have a full range of accommodation and shops catering to all tramping needs.

The Kepler Track is accessed from the Lake Te Anau Control Gates, either by road or a 50-minute walk from the Fiordland National Park Visitor Centre in Te Anau, or over the swingbridge across the Waiau River at Rainbow Reach, a ten-minute (12 km or 7.5 mi) drive from Te Anau.

Shuttle buses also operate during the summer months to entry and exit points on the track and a scheduled boat service provides access to Brod Bay.