In Te Waewae Bay, Southland, there is a stunning, remote, and long-curving beach, mostly backed by cliffs, from the Waiau River mouth to the west end of the bay. The beach is called Bluecliffs Beach (Rarakau), but this is a bit confusing for a first-time visitor. Most of the beach is backed by farmland and can only be accessed easily in three places.
From Tuātapere, take Papatotara Road, which connects with Papatotara Coast Road. Go west from Papatotara Road on the gravel Papatotara Coast Road to The Cliffs, a side road with several houses and a walking track to the beach. Continue on Papatotara Coast Road beyond The Cliffs, and you will finally see a sign for Bluecliffs Beach. The access is across a short bridge and next to a lagoon fed by Rowallan Burn. The final access point is on the edge of Fiordland National Park at the far west end of the bay. The park is accessed from the Rarakau car park at the start of the Hump Ridge Track (a Great Walk) and the remote South Coast Track along the coast into the park. You can also get to the beach from here.
Whichever access you choose, the beach is a superb remote experience. It is mostly undeveloped, with opportunities for swimming (stick to incoming tides), surfing, beachcombing, and hiking. The bay is also a marine mammal sanctuary. There is a reasonable chance you will see Hector dolphins and whales. If you do walk the beach, be aware that the waves can go up to the cliffs at high tide.