I'm thinking of traveling in New Zealand for a couple of weeks or months.
I plan to go on this trip around may or june.
So is it possible to fully enjoy this country while visiting it in Winter? I'm from Canada so I don't mind the cold, but can I still go hiking, etc.? I don't ski and snowboard, but I love walking et hiking.
Compared to Canada, New Zealand's winter temperatures are quite mild. New Zealand is a year-round destination. Auckland average high temperature is around 60 F (15 C) in winter. In Queenstown, South Island, it is about 48 F (9 C). The temperature ranges from 35-60 F, depending on where you go.
Winter is from June-August. It is usually less crowded and you can still enjoy most of the indoor and outdoor activities. Some watersports and hiking trails may not be open.
I suggest you take a look at New Zealand trails' article on What's the best time for hiking in New Zealand for tips and hiking trails in New Zealand.
New Zealand is known for its natural thermal pools and therapeutic spas. And if you like rugby, you may want to join in the fun with the locals when the All Blacks play. Here's the schedule: http://www.allblacks.com/Tickets/LionsSeries
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I have visited in fall, in spring, and in winter and enjoyed each season. The only downside of winter is that the days are shorter and the shadows are longer - so you will have less daylight to see things.