In 2015 and 2015 I walked all seven of the mainland New Zealand Great Walks that are actual walks. Thus, the only two I did not walk were the Rakiura Track on Stewart Island and the Whanganui Journey (on the mainland, but a canoe trip, not a walk).
The Great Walks are all relatively easy walks, with no scrambling required, thus appealing to people of average fitness and average hiking experience. They have also been chosen to represent the variations in scenery and ecosystems offered. The drawback to these walks are that all camping and hut spaces must be booked in advance via the DOC (online or in person), meaning that some of the most popular tracks sell out months in advance, most notably the Milford Track. I succeeded in getting tickets to all of the below walks a couple of days before departure, except the Milford Track (I finally booked with a commercial agency) and the Routeburn Track (I walked it in one long day).
There are plenty other hikes just as beautiful as the well-marketed Great Walks, some of them significantly more difficult. Unfortunately, I have, as of now, only walked a few of them.
Below a brief characteristic of each walk linking to an in-depth post:
Abel Tasman Coastal Track, New Zealand (2015)
Golden beaches and tropical vegetation. A very easy walk.
Heaphy Track, New Zealand (2016)
Pleasant walk through meadow and forest ending in a glorious walk along the Pacific coastline.
Kepler Track, New Zealand (2015)
Ascending to a ridge with fine views, the a pleasant walk through forest.
Lake Waikaremoana Track, New Zealand (2016)
A very atmospheric walk around a remote lake.
Milford Track, New Zealand (2015)
Unique animal and vegetation as well as wonderful waterfalls on the way to Milford Sound.
Routeburn Track, New Zealand (2015)
A glorious walk through meadows, ancient forests, waterfalls and lakes including a high mountain pass.
Tongariro Northern Circuit, New Zealand (2016)
Walk through active volacanic scenery passing craters and steamy lakes with the possibility of climbing Mt Doom.