Moeraki Boulders
Huge concrete eggs on the beach. Updated May 2023.
At Moeraki, a small fishing village near Otago, there is something you should be sure to include in your visit to New Zealand. The beach is strewn with huge, mysterious, naturally created concrete balls.
So pack a lunch and head to Otago. Even without the boulders, it is a great place to spend a few hours at the beach if the weather is nice.
What are the Mueraki Boulders?
The Moeraki Boulders are known as concretions, a type of naturally formed concrete. They formed about 60 million years ago and have spent most of the time since then buried under sand and water. In more recent times, they have become exposed due to erosion. However, some are only half exposed, with the lower half still buried in the sand. The boulders took about five million years to form.
The Moeraki Boulders are scattered along the beach. Some alone and others in groups. They are of various sizes. Some are 0.5 to 1.0 metre (1.6 to 3.3 ft) in diameter, but the larger ones weigh several tons and are almost three metres (9.8 feet).
The boulders were formed with mud, sand and clay and coated with calcite. The calcite was initially soft but hardened over time. If you want to see how this works, put a drop of glue into a box of sand. Shift the sand bank and forth, representing the waves of the sea, and then let the glue harden. You should end up with a hard ball of glue with a soft, sandy centre.
Some of the boulders have cracked open over time, and the soft centre has washed away, leaving the outer shell. These boulders remind me of broken and empty chicken eggs left over after
breakfast.
So, for some fun, get your photo taken as you hatch from an egg.
If you are taking a driving tour of New Zealand, be sure to take the time to stop and see the Moeraki Boulders. While on the beach, watch for seals and dolphins that frequent the area.
Camping on the beach is not permitted, and there is no on-site accommodation. There are campgrounds at Hampden, Moeraki and Trotters Gorge. Moeraki village has some private accommodations.