Hanalei Bay, Kaua'i.
Hanalei Bay Beach is a 2 mile crescent-moon bay near the Na Pali Coast with a picturesque environment and an excellent beach for swimming, snorkeling and surfing. More.
The town of Hanalei is a charming little place and a terrific base for exploring the Napali Coast.
Kalalau Valley seen from Pihea Trail, Napali State Park
Napali 'the Cliffs' Coast State Park: These magnificent green cliffs along 16 miles (24 km) of jagged north coast are so sheer that it is only accessible by land via the Kalalau Trail.
The Wailua Falls drop into the Wailua River in south central Kauai, a location that will be recognized by fans of 'Fantasy Island' TV show. Easy to reach by car, the falls are just north of Lihue. Wailua River is a favoured place for calm and spectacular kayaking.
Waimea Canyon is a magnificent 3,000ft (900m) deep river canyon with red lava beds resembles the Grand Canyon with added waterfalls, staggering views and great wilderness hikes (though hiking is not essential as lookouts, such as Kalalau and Pu'u O Kila, are superb if it's not foggy.More.
Tropical-looking Kee Beach, located at the western end of Na Pali Coast State Park on the North shore of Kauai, is the best snorkeling spot in the island. Its shallow lagoon offers great swimming, especially for families with children. The beach can have high surf during the winter, sometimes summer as well. Beware strong currents.
So...Aloha! from Hawaii but especially from Kauai!