An eye-catching sign with a mock kilometre marker turns the heads of travellers on road No.304 in Chachoengsao province. The sign reads "304 is edible - Khao Mai Pla Mun (newly harvested rice and fatty fish)".

It leaves many passers-by perplexed as to what it actually means.

Quite clearly it announces a campaign to promote a major food production source and food safety in the province, Traiphop Khotewongsa, a teacher at the Rajabhat Rajanagarindra University in the province explains.

No.304 refers to the road where the campaign is being held, he said.

More importantly, the road runs through the Bang Pakong River Basin, one of the country's major fertile grounds traversed by a network of waterways.

The road runs from areas which are the origins of the Bang Pakong River in Nakhon Nayok, Prachin Buri and Sa Kaeo. The river goes all the way through Chachoengsao and Chon Buri before emptying into the Gulf of Thailand.

So the No.304 area represents a chain of food from mountains all the way down to the sea.

The area provides food security and is a major source of nourishment for people in the river basin in the East. It is also a kitchen that feeds a large proportion of the country's population.

Mr Traiphop said the river basin is teeming with an abundance of food crops, rice and other staple foods.

Forests in Khao Yai national park supply water to rice farms in the region which is blessed with a great variety of rice strains. The diverse ecological system near the Gulf of Thailand also provides bountiful seafood. The Bang Pakong River Basin area is one of the last bastions of salt farms remaining in Chachoengsao's Bang Pakong district, Mr Traiphop said.

Celebrating the abundance nature has to offer, a market fair was organised from Jan 18-20 with the Rajabhat Rajanagarindra University as the main sponsor.

The event outside the municipal office in Phanom Sarakham district was a showcase of local produce grown along the "edible" route.

Organisers of the event want to spread the message that the river basin is a source of food security and brings together food from the five provinces in the river basin.

The term Khao Mai Pla Mun represents a gentle hint of nostalgia for the good old days when rice farming formed an integral part of the local culture and traditional lifestyles and when the country was rich in food and crops.

Every year, many Thais look forward to that special time when rice crops are ready for harvest. In and around Chachoengsao, harvest time is filled with joy.

Rice grains are picked fresh from the ears of rice and cooked as the rainy season begins to give way to the cool season.

The soft texture and the fragrant aroma of the cooked rice, particularly Hom Mali rice, coated with rice milk is irresistible.

A bowl of the newly harvested rice served with grilled fish caught towards the end of the water run-off season makes a perfect meal.

A catfish or a climbing perch from the rice fields are especially ideal.

During the cool season, some fish look for a place to hide as water run-off recedes while the cool weather is approaching.

Small fish born during the rainy season are now fully grown, with their bodies bursting with food nutrients they take in to prepare for the next rainy season.

When grilled on a fire, the fish flesh which is stretched taut by the cool weather is cracked open with drips of fat falling down to the fire below. The flavour of the fish is at its best during this season.

The term Khao Mai Pla Mun also refers to a period of wedded bliss enjoyed by a newly married couple.

Mr Traiphop said the event,was arranged for the first time this year and will be held every year from now on during the Khao Mai Pla Mun season during January.

"The area through which road No.304 meanders is a source of food for people. It provides safe food to consumers based on moral values, not just selling commercial products," he said.

Menus served during last month's market fair were prepared from local food ingredients picked fresh from farms and orchards in the Bang Pakong River Basin.

Dishes featured yod wai curry. Yod wai (young rattan shoots) is a local plant that grows wild and is free of harmful chemicals.

There were also dishes made of the famous snakehead fish from Paed Riew - the local and more popular name of Chachoengsao - and eaten with organic Hom Mali rice from Bang Khla district. Various local root crops were also available at the event.

Nikorn Chanthammapitak, the mayor of Phanom Sarakham municipality of Chachoengsao, stressed the importance of food safety.

"Food forms an important part of our everyday lives. If the food is safe to eat, people will be in good health.

"When we declared we will become the 'kitchen of the world', we cannot afford to produce food that is unfit for eating. Vegetables must be free of dangerous chemicals," Mr Nikorn said.

He said the municipality had joined forces with environmental groups to launch a campaign to control the expansion of the city and keep at bay the industrial sector which could threaten the safety of the food chain in the area.

Mr Nikorn said a campaign for food safety will be held every year with sessions to be organised to train food vendors and operators of restaurants on how to select ingredients and to prepare food.

School children will also be trained to become watchdogs to ensure food safety in their communities, Mr Nikorn said.

The idea came after the municipality took samples of food ingredients from local fresh markets for examination and found that they were contaminated, he said.

"I am happy that the networks for food safety in the five provinces signed up for this campaign," he said.

"We don't want the industrial sector to ruin our food production source. This is not intended as resistance, but we want the industrial sector to co-exist with agriculture to produce food," he said.

Over the past several years, the No.304 road has seen a big expansion of industrial businesses along its length. With the industrialisation has come factories and pollution.

Mr Nikorn said the event is aimed at making people aware that there is more to No.304 road than meets the eye. The "304 is edible" slogan is about the efforts to produce food in a safe and sustainable manner.

He said the area is also famous for growing premium quality mangoes for export and buyers must sign on to a long waiting list before they can buy the fruit.

Kingkaew Narintharakul Na Ayutthaya, deputy director of the non-profit organisation BioThai Foundation, supports the project.

The foundation is holding activities under the "Eating Changes the World" theme, with its main focus on consumers in big cities, particularly Bangkok, who are not food producers.

"We want city residents to be more involved in protecting this area of food production, too.

"They still have to depend on these food production sources in the agriculture sector while the small-scale farmers have to struggle to deal with various threats and risks from natural disasters and the government's national development plans which never take into account the needs of local people," she said.

Therefore, the foundation decided to step in to create and expand the networks to boost their leverage in protecting food supplies in their particular areas, Ms Kingkaew said.