Kauai is renowned for its white-sand beaches, with tourquoise water and dramatic mountain backdrops. In the winter months the north shore has some of the most famous and challenging surf breaks, but the sea is much calmer in the summer. There are reef-protected beaches that are great fro snorkeling and swimming year round, such as 'Anini or Makua (Tunnels) on the north shore. Keʻe, at the northern-most end of the road, is also reef-protected and very calm during the summer. On the south shore, Poipu has a calm, shallow section that's great for children.
One of the most beautiful beaches in the world is Hanalei Bay, north of Princeville. A two mile crescent of sand surrounded by tropical mountains, Hanalei has something to offer every water enthusiast. Surfing, swimming, boogie boarding, windsurfing and kayaking are some of the activities available, and the center of the beach has a pavillion with restrooms, showers, and lifeguards. Hanalei is divided into sections, with Black Pot Beach Park with its iconic Hanalei Pier at the mouth of the Hanalei River, Hanalei Pavillion in the middle, then Waioli (Pine Trees) which has a famous surf break, and Waipa. The town of Hanalei has shops, restaurants, and the historic Waioli church
If you are staying at Princeville, some of the resorts have paths down to Pali Ke Kua (Hideaways) Beach, which is excellent for snorkeling during the summer and is quiet and secluded year round. The paths are steep and can be slippery when wet, but it's worth the effort.
Lumahai Beach on the north shore was made famous by scenes in the movie "South Pacific", but is exposed to open ocean currents and is very hazardous for swimming. Great for walking and taking in the spectacular scenery, but avoid the water. A better choice for swimming, at least in the summer, is Haena Beach Park, with Mt. Makana (Bali Hai in "South Pacific") in the background. Across the road is the Maniniholo dry cave. The beach has facilities and life guards.
On the east shore is Anahola Beach Park, which is reef-protected and calm for most of the year. Lifeguards are on duty.
Also on the east side, you can't miss Kealia Beach as you drive north past Kapaa, with its dramatic surf. Kealia has lifeguards and restrooms, but is exposed to open ocean swells and strong currents. Unless you are an experienced surfer, it's better for strolling than swimming.
Beginning snorkelers and young children will enjoy Lydgate Beach Park. Rock-enclosed lagoons protect against surf but allow many reef fish to pass through, so a stunning variety of marine life may be observed with little effort in very calm water. Facilities, life guards and picnic tables are on site.
Culturally significant Salt Pond Beach Park on the west side has reef-protected, shallow pools of calm water that are also great for kids to swim in, adjacent to the salt-beds used by local Hawaiians for traditional practices.
At seventeen miles Polihale on the west side is the longest beach on the island, at the edge of the Na Pali coast. A four-wheel drive vehicle is necessary for access.
Not all beaches have life guards, so be sure to check ocean conditions before entering the water. The surf can change at a moment's notice, and what looks like a calm sea can quickly become hazardous.