Imagine that you are a flightless, semi rotund penguin like critter. Now imagine that your singular goal is to go to a beach and carve out a small hole in the sand for your mate and young to sit in. Not just any sand or any old beach mind you. You must go to a specific beach on a remote coast on New Zealand's north island and not just any old place on that beach. You must go to a specific section no more than a 100 meters wide.

Now you can't go anytime you want, you can only gain access to your treasured section of beach for a short period around low tide. Now imagine you're not alone in your quest; in fact others just like you have come from all over the world to share in the sand digging splendor. Just as the tide exposes your quest you arrive and proceed to the designated spot where you busily begin digging and establishing a perimeter to ward off the throngs of other sand diggers just like you.

While you dig, your mate and children distract the throngs of other diggers with fanciful displays and much noise making. At last the hole is ready and you busily jump in to the sandy hot tub you've just made. You see, you're at the hot water beach on the Coramandel Peninsula and if you're lucky you've dug a hole above a bubbling hot spring on the beach and the scalding hot water is mixing with the cold ocean waves to make a perfect hot tub!

Gradually all of the available space is taken by holes that share sand castle walls and in each hole is a family basking in the perfect glory that is a natural hot tub on the beach.

Aint life grand!