What the longest night of the year in new Zealand?

Answer 1

In 2010 the Southern Solstice takes place on the 21st of December at 23:38 UTC, which in New Zealand Daylight Saving time is 12:38 on the 22nd therefore the longest day for New Zealand for 2010 is December 22.

Answer 2

The longest day of the year in any region is called the Summer Solstice.

The time varies for each region, but the date is typically the same: July 21

For Auckland, New Zealand, the Summer Solstice in 2014 occurs on July 21, 2014 starting at 2:30pm.