New Zealand has nine Great Walks in total—with five on the South Island, three on the North Island, and one on Stewart Island—centered in some of the country’s most iconic scenery. They are fastidiously managed by New Zealand’s Department of Conservation (DOC), with well maintained trails, plentiful signage, rangers on duty during the high season, and DOC huts and campsites of the highest standard. 

Averaging 3–4 days in duration, the Great Walks can be completed solo or with a guide. Guides are expensive but provide local knowledge, cushier private huts, tastier meals (and drinks), transportation, and will help lighten your load. Make sure to plan ahead: the DOC limits the number of hikers on the Great Walks with a strict permit system. Some of the most popular hikes, such as the Milford and Routeburn Tracks, are fully booked months in advance. 

Great Walks on the South Island

Milford Track: 53.5 km; 4 days; moderate. Annual visitors: ~14,500.
Starting at the head of Lake Te Anau, this awe-inspiring trek passes through temperate rainforests over Mackinnon Pass and ends at celebrated Milford Sound. During the high season the Milford Track can be walked only in one direction: from Glade Wharf at Lake Te Anau to Sandfly Point in Milford Sound. The trek must be completed in four days/three nights. Camping is not permitted and boat connections are available on both ends. Rain falls over 200 days a year in Milford Sound so pack accordingly. For further information, see the Department of Conservation permits online, Milford Track guides, and transport.
 

Routeburn Track: 32 km; 2–3 days; moderate. Annual visitors: ~16,000.
From beech forest and waterfalls up to the Harris Saddle and alpine lakes, this is the second most sought after Great Walk. Close in proximity to the Milford Track, the Routeburn gets considerably less rain, especially on its eastern side. It is a one-way trek requiring transportation; the majority of walkers start at the Divide and finish at the Routeburn Shelter. For those short on time, Key Summit is an excellent day hike (3 hours roundtrip from the Divide). For further information, see the Department of Conservation permits online, Routeburn Track guides, and transport.
 

Kepler Track: 60 km; 3–4 days; moderate to challenging. Annual visitors: ~9,000.
The Kepler Track doesn’t quite garner the attention of the Milford or Routeburn Tracks, but there’s an argument it’s the most beautiful. Why? The Milford and Routeburn pass through a greater diversity of ecosystems—particularly rainforests—but neither can top the alpine section of the Kepler. One of the best challenging day hikes in New Zealand is round trip from Te Anau up to the Luxmore Hut.
 

Abel Tasman Coast Track: 54 km; 2–5 days; easy. Annual visitors: ~31,000.
Abel Tasman National Park—with its white sand beaches, crystal clear water, lush native forests, and granite rock formations—is a natural paradise. The full Abel Tasman Coast Track is worthwhile, but there are also good access points along the route for a more targeted trip. The Park is extremely popular, but the DOC operates 18 campsites and four huts, and there are a handful of private accommodations. To get away from the crowds, the northern section of Abel Tasman beyond Totaranui and the reach of the water taxis is stunning and gets far fewer visitors (the coast is rougher and more exposed). Many kayaking options are available in Abel Tasman National Park, including multi-day trips.
 

Heaphy Track: 78 km; 4–6 days; moderate to challenging. Annual visitors: ~5,000.
This lengthy walk through Kahurangi National Park begins at the junction of two rivers and passes through lush forests and nikau palms to the roaring seas of the Wild West Coast. The bird spotting is exceptional, and the Heaphy Track is one of the only Great Walks accessible year-round. It is a one-way trek and guided trips are available. The DOC is currently running a trial period and allowing mountain bikes on the track through 2013 (allow 2–3 days for the ride). 
 

Great Walks on Stewart Island

Raikura Track: 37 km; 3 days; moderate. Annual visitors: ~1,500.
Get off the beaten path on untamed Stewart Island, which is a 20-minute flight from Invercargill or a one-hour ferry from Bluff. Aside from the settlement of Oban, the starting and ending point of the trek, Stewart Island is almost entirely undeveloped and blanketed by thick, native vegetation. The scenery is not as jaw dropping as some of the other Great Walks, but the Raikura Track is pure New Zealand wilderness and gets the least visitors with only 1,500 trekkers per year.
 

Great Walks on the North Island

Tongariro Northern Circuit: 
50 km; 3–4 days; moderate to challenging.
Annual visitors: ~5,500.
This Great Walk circumnavigates the active volcano Mount Ngauruhoe in Tongariro National Park, including the famed Tongariro Crossing. The Crossing can be completed as a day hike, which is a far more popular option than the full Circuit. The weather can be tricky and the summer hiking season in Tongariro is from December to March.
 

Lake Waikaremoana Great Walk: 46 km; 3–4 days; moderate. 
Annual visitors: ~5,600.
The majority of this trek skirts the western shoreline of magnificent Lake Waikaremoana through the dense and varied forests of Te Urewera National Park. It is a one-way trip and ground transportation is readily available.
 

Whanganui Journey: 145 km canoe or kayak; 5 days on average. Annual visitors: unavailable.
This gentle trip down the Whanganui River from Taumarunui to Pipirki, once used by the Maoris, passes through a wide range of beautiful terrain. There are 11 DOC campsites and 3 huts spaced out along the river, and the trip can be completed either with canoes or kayaks. For a shorter, 3-day option, put in at Whakahoro.