From the north end of Waihi Beach, you can access the Orokawa Bay Track. It’s about a 40 minute walk around the cliffs of Rapatiotio Point to get to one of the prettiest bays in NZ, with a beautiful beach overhung by big mature pōhutukawa trees.
By all means stop there and do beachy things. Note that the beach is unpatrolled if you swim. But you can also walk for another 40 minutes or so to the modest but pretty William Wright Falls, or for about 90 minutes to Homunga Bay.