You better pack your snorkeling gear before you head on down to Kahalu'u Beach Park. This beach park, sitting just 15 minutes south of Kona on the west coast, is home to some of the Big Island's best snorkeling. You'll also want to pack some water shoes.
This beach park has plenty of parking, but the popular beach is usually packed. Just off the parking lot, you'll find bathrooms, food vendors, picnic tables and a pavilion. And you'll soon notice that the beach is made up entirely of lava rock with just a few sandy patches. You'll need those water shoes to get in and out of the water without any discomfort.
Carefully navigate yourself into the deeper water, dunk your head underneath and you'll be transported to another world. Radiant tropical fish flit about to give the dark underwater scene streaks of color. And you're very likely to run into a sea turtle in the waist-high water.
Sea turtles have an interesting life cycle. They are born carnivores. The tiny little turtles that race to the water from their sandy nests feast on small fish and crabs. The turtle then becomes an omnivore as it continues to grow. Adult sea turtles become exclusively vegetarian, and these friendly creatures love to feast on the grassy rocks at Kahalu'u Beach Park.
It is illegal to touch sea turtles in Hawaii. Law enforcement gleefully enforces this law, and locals won't take too kindly to any touching, either. And you're surrounded by locals at this popular beach. The oils in your skin can degrade the turtle's shell. Make sure you keep your distance from the feeding turtles because currents and waves can throw you into the cute little critters. And make sure to take that selfie from a distance.
The water here is protected by a rock wall. You'll find the snorkeling conditions clear and calm out in the depths, but the water can be cloudy near the shore. Tropical fish like to feast on the seaweed kicked up by tourists in the beaches few sandy parts. Don't be tricked into staying in this sandy water. Head to a deeper section and you'll likely be surrounded by schools of fish.