If you want truly picturesque, then the Poor Knights Islands are all you could ever ask for. A small collection of land masses east of the Northland coast (about 50 km/31 miles from the city of Whangerei), these islands are part of a marine reserve and consist of the look-but-do-not-touch variety. This means that you won't be able to anchor your boat without the right permits. Despite the natural beauty of rock formations like High Peaks Rocks (which claw like eroded fingers from the waves), the biggest inspiration is what's under the water.
Considered one of the top scuba diving sites in New Zealand, the Poor Knights Islands benefit from the diverse marine species that accompany the subtropical currents. It would be no surprise to see kelp, sponge, coral, eels, dolphins, stingray, and any of the over 125 species of fish during a single dive. The colorful diversity is a must and can be viewed even by snorkelers and novice divers; we suggest finding a dive or tour operator that works the area (we've included some below) and use their knowledge to your advantage. No matter where you dive, the clear and pristine waters and variety of sea life are world class.
There are also kayaking and canoeing options to fill a full day trip with a chance to see all of the different rock formations. For more information on the islands, browse our included links.