"People living here have been here 60 years, on average," Kang Myung-song, 67, the president of the island's residents' community told visiting reporters last week. "People don't want to leave. It's our hometown."

Kang remembers the events of November 23, 2010, like yesterday. "There was an unbelievable noise - deafening, indescribable, a noise I'd never heard before," he said. "I saw smoke and ran for the shelter."

Another resident, 83-year-old Kim Yoo-sung, was stunned when every window and door of his house suddenly blew in.

But he knew what the noise was - a veteran of the Korean War, he'd heard artillery before.

It had already been a tense year. That spring, a South Korean corvette had been sunk by a North Korean submarine.

On the bright morning of November 23, South Korean forces on Yeonpyeong were carrying out artillery drills, firing into open waters west of the island. North Korea telexed South Korea, demanding a halt.

When South Korea ignored the demand, North Korean rocket launchers on the mainland and artillery in caves on a nearby island let fly.

A barrage screamed into Yeonpyeong. Buildings were shattered and hillside foliage blazed. South Korean artillery on the island replied. The noise continued for more than two hours.

At the end of it, four South Koreans lay dead and 16 were wounded.

Two years later, the trauma lingers. "People here can't sleep right," Kim said. "People wake up in the middle of the night in fear."

Signs of the attack are difficult to miss in Yeonpyeong's little port. A gaping hole in a waterfront wall has peaceful hands painted around it.

A chunk of shrapnel-scarred masonry lies in a government office car park.

A block of cottages shattered in the barrage - their inhabitants were luckily working in the fields at the time - stands in permanent remembrance.

"We have to preserve it as it is," said Kang. A museum is being built over the blackened ruins. While many Yeonpyeong residents fled after the attack - Kim decamped to the port city of Incheon, where he lived for three months - most returned.

The island's population has increased. Incoming military and their families have bolstered the garrison, and construction workers are upgrading defences and rebuilding nearly 40 homes destroyed in the attack. Students also visit to learn about security.

The island bustles with martial activity. It is garrisoned by some of the fiercest troops in Asia - South Korean marines - who are digging in deep.

Firing points overlook crossroads, artillery is positioned in bunkers in rugged hills and scenic beaches are wired off.

A tank squats by a roadside and an armoured troop carrier lies in wait, its nose painted like the snout of a shark.

Seoul refuses to divulge troop numbers, but a marine admitted Yeonpyeong's military population now outnumbers its 1,987 civilians.

Could there be another attack? Yeonpyeong and other South Korean islands off the North Korean coast - some were used during the war as launch points for partisan operations - threaten Pyongyang.

Moreover, the Yellow Sea border, the Northern Limit Line, was unilaterally drawn by the United Nations at the end of the war.

North Korea has challenged the line since the 1970s and there were naval clashes in the area in 1999, 2002 and 2010.

Goh Young-hwan, a North Korean defector who works for Seoul's Institute for National Security Strategy, said North Korean leader Kim Jong-un needs to bolster his credentials.

"The only way to secure his leadership is operations against South Korea," he said.

"It could be a submarine attack or a landing on an island near the sea border."

But the islanders stay defiant. Asked what message he would like to send to those who planned the bombardment, Kim was to the point. "I'd like to beat the hell out of them!" he said.