Carved out by the 20 mile-long river sharing its name, Wailua River Valley offers boating, tubing, and kayaking. The river flows into the Wailua and Opaekaa falls. The valley offers several different hikes to waterfalls and lookouts in the area. The Wailua River itself is the 3rd longest river on Kauai, so water activities here can take up your entire day.
Major landmarks in the Wailua River Valley include the Keahua Arboretum, several heiau (shrines), and the Sleeping Giant trail. Read more about the Wailua River Valley and the activities available there here.