The wooded mountains make it a site of outstanding natural beauty, but it is the freshwater marsh and coastal habitats, that gives the park ecological significance. The offers fine sandy beaches, spectacular caves, superb mountain viewpoints, offshore islands, forest trails, boat excursions, and estuarine and mangrove habitats, all within a relatively small area.

Wildlife

The park still supports a population of Serow and blackish goat antelope. There are three species of primates: dusky or spectacled langur, crab eating or long tailed macaque, and the slow lorris. Other mammals found are the barking deer, malayan pangolin, fishing cat, common palm-civet, malayan porcupine, javan mongosse, siamese hare, grey bellied squarrel. Dolphins are sometimes sighted in the coastal water.

There are around 300 species of birds recorded seen in the park. The large number of species found in a relatively small area can be attributed to the unique diversity of habitat, and because the park is located on the east Asian/Australian flyway of birds. Migratory birds account for about half of the recorded species.

Sheltered in one of its several caves up in the hills is a royal pavilion, the main attraction for travelers prepared to go the distance. Tham Phraya Nakhon, a cave high up in the mountains of Khao Sam Roi Yot National Park in the coastal province of Prachuap Khiri Khan is a major attraction for those visiting the park, but the climb uphill is very testing, not meant for the faint-hearted.
The best time to visit the cave is around 10 a.m. when the pavilion is lit by soft rays of the sun.

Apart from Tham Phraya Nakhon, the park has other caves such as Sai which features odd limestone formations, stalactites and stalagmite. Another fascinating cave is Tham Kaew, which has formations of calcite crystals. They glow in the presence of light.

If you do not enjoy exploring caves, the park offers other recreational opportunities such as kayaking, boat cruise on Khlong Khao Daeng canal to observe wildlife _ birds, monkeys and monitor lizards. The best time for the hour-long cruise is early morning to late afternoon. And do not miss the evenings when the sun dips below the horizon of green rice fields.

For a good view, climb atop Khao Daeng, a short walk from the park office building. Watching the sun rise over the sea is particularly spectacular.

In addition, the park is home to some 300 bird species of which 180 are migratory. The best months to watch birds are September to November.