Phra Chuthathut Ratchathan
Phra Chuthathut Ratchathan, which was named after Prince Chuthathut who was born here, is the only palace located in the sea. King Rama V had it built in 1892 as a holiday retreat and a convalescence home for his wives and children. The funds for the construction of this palace came from his private treasury.

The king loved to visit Ko Si Chang to admire its magnificent scenery and tranquil atmosphere. However, in the later years, the island served as a big cargo station where numerous transactions with foreign ships took place.