Hin Ta Hin Yai is located in Hat Lamai, Tambon Maret. This natural phenomenon originates from the granite eroded by sea water and heat to form weird boulders. There is hearsay among the locals that a long time ago the grandparents, Ta Khreng and Yai Riam, natives of Nakhon Si Thammarat, travelled by sail boat to Prachuap Khiri Khan for proposing the marriage of their son to a daughter of Ta Monglai. Unfortunately, a strong storm sank their boat in Hat Lamai and the grandparents drowned. Their bodies were washed ashore and turned into the stones as seen nowadays.