We got to see a lot of both Islands over two weeks. May have done better to slow down. Could easily spend two weeks on each island apiece. My brother has back and heart issues, so hiking was out. I thoroughly enjoyed the 2 – 4 hour hikes including some arduous climbs–climbing Rangitoto or the main ascent at Rob Roy Glacier Track I would say is similar to setting the treadmill at 3.5 with an incline of 10 for 30 min. You don’t have to go that fast and I talked with a couple in their mid70s who made it up Rob Roy. The views are worth the work, as I watched a piece of ice fall off the glacier while eating my lunch–wow! And when was the last time you caught five trout 3.5 lbs or larger in two days? That is doable in NZ. Recommendation to tourists–there is a lot to do, we picked one key thing each day, sometimes different due to my brother’s and my different interests or physical abilities. Each day was special.