Someone mentioned the Milford Track. It is definitely an extraordinary experience, and not that hard (but still needs to be taken seriously). Unfortunately it is usually fully booked many months in advance, and you’d be lucky to find a spot for February. However there are lots of other tracks well l worth walking if you Google DoC Great Walks. I think it would be difficult to fit one into a 10 day trip though.

Able Tasman was mentioned, and that would be doable, but would take at least two hectic days out of your trip. It’s a big drive north of Nelson with a windy mountain road that always takes longer than you think. You couldn’t do Golden Bay (top end of the Able Tasman track) without driving to Collingwood and Farewell Spit. The spit is one of those never forget as long as you live experiences.

To do the Farewell Spit, drive to the café and park, then walk along the beach for a mile before turning north on a track across to the sea side of the spit. Sand dunes that go on forever and amazing windblown patterns in the sand. Sand in your camera can be a problem, so take a plastic bag.

Not far from the Spit is Cape Farewell. Look out from the platform, then walk up the hill on your left to see what was underneath you. I’ll give you a clue… Nothing!

Also in the north west is the drive from Westport to Karamea. Great but too far out of your way for ten days. You could perhaps drive up to the Denniston Incline just north of Westport.

http://en.wikipedia.org/wiki/Denniston,_New_Zealand

Taking a leap, the road north of Christchurch along the east coast to Kaikoura is a must see. Marlborough – where I live — is one of the sunniest places in New Zealand. Lots of wine tasting, but Peter Jackson’s Aviation Heritage Centre is worth a visit. I filmed inside it last week in fact, and got some OK shots and footage.

http://www.flickr.com/photos/trevor-dennis/sets/72157632426573957/