Hin Ta Hin Yai

Hin Ta Hin Yai, known as Grandfather and Grandmother Rocks, is a famous natural rock formation at the southern end of Lamai Beach in Maret, Ko Samui, Surat Thani Province. The coastal granite boulders naturally resemble male and female genitalia, creating a distinctive landmark. Formed by natural erosion, the site is associated with a local folklore legend and offers sea views, small sandy coves and photo opportunities, making it one of Ko Samui's most visited natural attractions.

Visitors can expect a coastal granite rock formation at the southern end of Lamai Beach with two main boulders - Hin Ta (Grandfather) and Hin Yai (Grandmother) - set on a rocky shoreline with clear sea views and small sandy areas. There are paved walkways, viewing platforms, steps leading down to the rocks and shoreline, and informational signs explaining the local legend. The surrounding area has souvenir shops and food stalls, and visitors can walk around the rocks, take photographs, and view the Gulf of Thailand.

The site is associated with a local folklore legend about an elderly couple, Ta Kreng and Yai Riam, who were shipwrecked in Lamai Bay while traveling to arrange a marriage for their son and were turned into the rocks as a memorial. The rocks were formed naturally by coastal erosion of granite.

Hin Ta Hin Yai is a well-known cultural landmark in Ko Samui folklore, often regarded locally as a symbol of fertility. The legend is shared with visitors through signage and is part of the island's oral tradition and identity as a natural attraction.