The scenic alpine route from Christchurch to the West Coast that leads through the Porters' and Arthur's Passes is spectacularly scenic, and crosses some excellent hill-walking land too.
There are many short and day hikes in the vicinity of Arthur's Pass village, but perhaps the most unique and also very accessible site is twenty kilometres or so west from Springfield, just past the Porters' Pass towards the Arthur's Pass. It's called the Castle Hill, and it's an extensive area of limestone outcrops forming a veritable labyrinth on a hillside.
We drive there from Springfield on a sunny and pleasantly warm day and spend at three hours there: but you can go for as little as half an hour and it will still be fun.
We walk around, attempt bouldering, pose on and hide beneath the rocks which vary in size from small stones to larger than a house. The variety of shapes is fascinating: smooth, Henry-Mooresque, organic, the young sharp edges of just-cracked rock worn to flowing curves by the years of wind and water.
To the side of the main three groups of outcrops is a raising hillside, with more boulders and a high ridge behind which one of the Narnia films was partially made. We set off to climb it rather fool-hardily.
The path up is relatively short but extremely steep: at times I feel I am going to actually fall off backwards and luckily it is dry and we eventually make it: it is much higher than it appears, or at least it feels much higher. We scramble down (partially shuffling down on our bottoms, which is fun on the tussocks of grass and less fun when one hits a stone).
After three hours in the sun on the hillside and all this hillwalking we are tired and sun-dazed, but the views were fabulous, the boulders fascinating and the whole experience a fitting last day to our whole New Zealand trip. Very much recommended if you are in the area and easily worth a day trip from Christchurch too.