In general, it is hard to freedive for depth on any of the Hawaiian islands. Most locals who want to practice take a boat out to deep water. The one well-known exception to this is Honaunau bay on the Big Island.

Honaunau, also known as "Two Step Beach", is protected from most currents and swell, and offers quick access to 50-70m depth.

Visibility here is usually incredible, from 20-35m, because the shoreline is black lava rock rather than sand. The water temperature is 25-27C.

Another amazing feature of Honaunau is that the bay is a favorite place of spinner dolphins, who will jump out of the water and do spins for fun, often all around you while you are freediving.

There are some cultural sensitivities to be aware of. Honaunau is an important place for native Hawaiians, and no commercial activity is supposed to take place in the bay, so technically, you can freedive with a buddy here but not with an instructor. Also, there are a couple of locals who will abuse people over a megaphone who they see close to the dolphins. As per the Marine Mammal Act, don't swim towards dolphins and certainly don't chase or harass them, but if they swim close to you and you get yelled at, don't engage and just keep doing what you are doing.