Queenstown itself is a little village with lots of shopping (and really good fish n' chips), but you can take very short distance day trips to places like
Lake Wanaka where there's sky diving, bungee jumping and jet skis. In town there's a place called
Skyline Gondola Restaurant and Luge which is exactly what it sounds like. You can take the gondola up or hike up the mountain and luge your way down. Right on that same hill there's also a place over the side of the mountain where you can sit in a big wine barrel hot tub called
Onsen Hot Pools . And if you have the time, you can take a longer day trip to
Milford Track. I took Juicy Tours, which seemed like the popular option, and we left at 6am and got back around 10 at night, but an amazing experience.
You don't need to necessarily book everything before you get down there because there's an enormous sports complex in the middle of town where they'll consult you on the best activities and make your weekly itinerary for you. The name escapes me, but you seriously cannot miss it - biggest building in town.
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There are so many fun and exciting things to do in Queenstown. Not sure what you have in mind but very easy to plan once you get there. Jet Boating, Para-sailing, Paragliding over the city, Kawarau Bridge Bungy Jump (original buggy), Rock climbing nearby on Queenstown hill and other areas (self-guided or via agency), Skydiving in Wanaka, hang-gliding off remarkable range, great day hike on Ben Lomond Track, and white water rafting. Many places will bundle these adventures together for a better deal. Very easy to plan on arrival and lots of people to help plan your trip. If you have an extended stay and enjoy hiking / backpacking there are many famous tracks you can do that take 3-5 days close by. Many of these should be planned in advance such as Milford Track (amazing) and Routeburn Track. Less crowded and a short drive will take you up west coast where you can hike up to Welcome Flats Hut - beautiful place with natural hot springs to soak in once you get there. Then a short drive from there would take you to Fox Glacier where you can explore the glaciers.
If you go in winter (our summer) you can find some great skiing or snowboarding and also good heli-skiing. In addition, there are amazing mountaineering trips (climb Mount Cook) and also ice climbing classes/ courses. ( Copland Track is a good mountaineering traverse) Another awesome place is going to Mueller Hut which is about a 5 hours hike. Beautiful setting with glaciers and snow all around and the sound of avalanches in the background.
All depends on how much time you have. We took our family there for a year and still couldn't do half of the amazing things there. Another cool trip is to fly out of Invercargill to Stewart Island (8 seat plane) and land on beach and hike out staying in various huts. We even saw a Kiwi bird while hiking out.
Most of this stuff can be found online via quick searches but this should provide you with a few ideas. Cheers-
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