One of a variety of preserved fishes which originated in the old days, Pla Ra is made in Sri Songkhram District an area around the Sri Songkram River which is rich in numerous freshwater fish including striped catfish, Siamese giant carp, spotted featherback, great white sheatfish, as well as those found only in the Khong River and its branches such as Mekong Giant Catfish, thryssa, etc. It is believed that these fish swarm into the rivers to feed on the salty soil and to breed.

To make pla ra, the fish is cleaned and cut into pieces. Then it is mixed with salt and rice bran. The mixture is then stuffed into a big water jar, topped with a piece of wood to prevent the fish from becoming bloated, and left for 2 to 3 years before being eaten.

Pla Ra has become a well-know dish among Thais and foreigners alike. They are canned for export now. Pla Ra brings extra income to the villagers.