One of the must see places in New Zealand is Cathedral Cove.
The hike is very long and takes you through forests, along the coast, and winding up and down many hills and stairs. 
Be sure to bring lots if water and snacks on your hike to the cove. 
Once you are at the beach at the end of the hike to the left is a huge cove and a beautiful sight to see. 
Traveling Gem 