he Phraya Nakhon cave is best known for the Kuha Karuhas pavilion in the main chamber. The pavilion was built at the end of the 19th century for the visit of King Chulalongkorn the Great (Rama V). Later, King Prajadhipok (Rama VII) and the present King of Thailand, King Bhumibol Adulyadej (Rama IX) also visited the cave.
The main chamber contains the signatures of both King Rama V and King Rama VII on the wall. The best views of the pavilion can be had early morning, when most sun light enters the cave through the open ceiling. The provincial seal of Prachuap Khiri Khan contains an image of the Kuha Karuhas pavilion.