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Immediately north of the national historical park, concealed within a (usually) placid bay, are a series of ridiculously vibrant coral gardens where the reef and marine life seem locked in a permanent race to outstrip each other with the gaudiest color palette. From above the water, your only indication of the action is the presence of boats and crowds gathering at the titular two steps.

There's no beach here – snorkelers use a stepped lava ledge beside the boat ramp to access about 10ft of water, which quickly drops to about 25ft.

Once you’re in the water you’ll feel like a supporting cast player in Disney’s The Little Mermaid. Visibility is usually excellent, especially with the noon sun overhead; good-size reef fish and a fine variety of coral are close to shore. The predatory ‘crown of thorns’ starfish can be seen feasting on live coral polyps. Cool, freshwater springs seep out of the ground, creating blurry patches in the water. Divers can investigate a ledge a little way out that drops off about 100ft.

The best time to go is during rising tide, when there are more fish. High winter surf means rough waters. The morning is also always better for undersea wildlife watching.

A privately operated parking lot costs $3. You can also park in the national park lot ($5, but you can go in and out for 10 days) or try to squeeze in along the road's shoulder.