Cathedral Caves and Waipati Beach
You'll find the turnoff to the Cathedral Caves 5km from Tautuku. It's a 45min walk from the car park. First walk to the beach and then through ferns and kamahi to the caves. Named after an English Cathedral, they are large caverns with wide mouths cut out of the rock over centuries. You'll need to check out the tides as the caves on Waipati are only accessible at low-tide. You may also wish to check out the McLean Falls once you're in the area. There is a sign just outside the carpark which will direct you 5km up a dirt road. Then it's time to dump the car and take a 30min stroll.