Tham Thong Beach

Tham Thong Beach sits in Pak Khlong subdistrict, Pathio district, part of a long stretch of coastline that runs north toward Bang Boet in neighbouring Prachuap Khiri Khan province — locally the whole stretch is sometimes called Bang Boet-Tham Thong Beach. What sets it apart from Chumphon’s other beaches is the sand dune running behind it: roughly 10 km of coastal dune covering about 790 acres, with the highest points reaching around 20 metres above sea level, formed by monsoon storms depositing sand over thousands of years. It’s regularly described as the largest surviving sand dune system on Thailand’s coast.

The sand itself is fine enough that you sink in noticeably with each step in the open dune areas, but a dune forest of over 160 native plant species — species adapted to grow in shifting sand, some of them rare elsewhere — holds much of the terrain together with root systems that also make walking easier once you’re among the trees. It’s an unusual landscape for a Thai beach visit: part shoreline, part semi-stabilised sand hills, with fishing boats moored near a small pier toward the southern end where a short walk of about 500 metres leads to a small cave worth a quick look.

Watch out: There’s essentially nothing built up around this beach — no beach chairs for rent, no strip of restaurants, and only a couple of small resorts nearby (Tham Thong Resort and Baan Kamnerdploy Resort). Bring your own food, water, and sun protection.

Insider Tip: Visit outside Thai public holidays for the quietest experience — this beach sees far fewer visitors than Chumphon’s more developed spots like Thung Wua Laen, which suits anyone after an empty stretch of sand rather than beach-club amenities.

Most of the surrounding village works fishing, and the coastline is protected and undeveloped rather than being geared toward tourism. That’s the appeal and the limitation in the same package: genuinely untouched dune scenery, but plan to be self-sufficient for food, shade, and water while you’re there.

Ban Boet Beach continues the same coastline into the Prachuap Khiri Khan side, and Khao Laem Ya is the headland hill nearby. The Chumphon destination guide covers the rest of the province’s beaches for planning a longer coastal trip.