Hanapepe is small town on the southern coast of Kauai. It is the location of the Hanapepe salt ponds where a group of families make sea salt. Hawaiian sea salt is made at other locations, but according to the Hanapepe salt makers, Hanapepe's is the only place where it is made in a traditional, labor-intensive way.

Production
The salt is produced by using the sun to evaporate the water out of salt water, leaving behind the dissolved salt and minerals. It's done in ponds (lo‘i) whose beds are lined with a specific type of red clay (alaea). The coloring comes from the iron oxide in the volcanic clay.

There are an entire list of guidelines, rules, and traditions surround the production of the salt. Everything from the timing on setting up the ponds to when to harvest are determined by tradition and experts. Menstruating women aren't allowed around the ponds, nor is food and drink.

The salt is usually separated into three grades: white, pink, and red. The white salt is on the top of the bed, the pink in the middle and the red on the bottom. The process is heavily influenced by the weather and seasons. If the weather cooperates, the ponds can be harvested up to three times per year.

Cultural Aspects
The salt is used for seasoning, food preservation, and food preparation, as you've expect. It's also used for medicinal and ritual purposes.

Hanapepe salt cannot be purchased, in stores or otherwise. The families that produce the salt specifically only use the salt for gifts or trade. That gives it a little special allure as you can't just go to Kauai and score some salt, you've got to find a way to get it. Some people will tell you that's because of an old agreement between families or out of respect for the importance of the salt. Other people will tell you that it's because of an old agreement with the state, which owns the land the salt ponds are on, and doesn't want the land commercially exploited.

Miscellaneous
When Captain Cook visited the Hawaiian islands, he was gifted with traditional sea salt. In his journal, he bemoaned the "dirty" salt he was given.

If you're going to fly off the island with some Hanapepe salt, you may take a little extra time to get through security screening. When you're going through, they'll likely ask you to let them test it to make sure it's not meth, which is apparently quite the issue on Kauai. They take a little pinch out of your container and put it on some paper. They then put a drop of liquid on it, which changes color depending on whether it's meth. The TSA agent that tested mine helpfully shared some tips on using the salt while running the test.