Due to countless twists and turns, the exact length of the New Zealand's coastline is impossible to measure. But, it's estimated to be between 15000 and 18000 kilometers. Although the North Island is smaller than the South Island, it has a longer coastline due to numerous inlets, bays, harbors, flords and estuaries.
The New Zealand's coastline has numerous lighthouse(s) that play a key role in keeping the ships safe from harm. The year 2013 marks the 100 years of the development of New Zealand's Maritime Radio Service. And, also, the year marks the centenary of the Castle Point Lighthouse on the Wairarapa coast.
New Zealand Post commemorated the Castle Point Lighthouse with the release of a 70 cents stamp on 4-Sep-2013 in its New Zealand Coastlines Stamp Issue. The New Zealand Coastline Stamp Issue celebrates five areas of New Zealand's Coast and the lighthouse(s) that monitor them.
The detail(s) about the Castle Point Lighthouse is available in my earlier post #0181...