Boxing Day, 2004.

When the earthquake struck at 06:30 (01:00 GMT), I was on a ferry, headed towards Havelock – an island in the Indian archipelago of Andaman and Nicobar.

Known for its silver sand and clear blue waters, the Radhanagar beach there had recently been crowned "Asia's Best Beach" by Time magazine.

My best friend from college and her family had lived in Port Blair, the capital of the archipelago, for a decade and a half, but this was my first visit to the islands, where I had arrived on Christmas Eve.

We had planned to spend three days in Havelock and in the morning we packed snacks and sandwiches, gathered excited children and headed out to catch the ferry from Phoenix Bay jetty in Port Blair.

Not wanting to miss out on anything, I was standing on the front deck, looking around, when disaster struck.

Just as we pulled out from the harbour, the boat lurched and suddenly the jetty next to where we had boarded crumpled and fell into the sea. It was followed by the watchtower and an electricity pole.

It was an extraordinary sight. Dozens of people standing alongside me watched open-mouthed.

Thankfully, the jetty was deserted at the time so there were no casualties. A boat was due to leave from there in half an hour but the travellers were yet to arrive.

A member of the boat's crew told me it was an earthquake. At the time I didn't know, but the 9.1 magnitude quake was the third most powerful ever recorded in the world - and remains the biggest and most destructive in Asia.

Occurring off the coast of northwest Sumatra under the Indian Ocean, it unleashed a devastating tsunami that killed an estimated 228,000 people across more than a dozen countries and caused massive damage in Indonesia, Sri Lanka, India, Maldives and Thailand.

The Andaman and Nicobar islands, located just about 100km north of the epicentre, suffered extensive damage when a wall of water, as high as 15 metres (49 ft) in places, hit land just about 15 minutes later.

The official death toll was put at 1,310 – but with more than 5,600 people missing and presumed dead, it's believed that more than 7,000 islanders perished.

While on the boat, however, we were oblivious to the scale of destruction around us. Our mobile phones didn't work on the water and we only got snippets of information from the crew. We heard about damage in Sri Lanka, Bali, Thailand and Maldives – and the southern Indian coastal town of Nagapattinam.

But there was no information about Andaman and Nicobar - a collection of hundreds of islands scattered around in the Bay of Bengal, located about 1,500km (915 miles) east of India's mainland.

Only 38 of them were inhabited. They were home to 400,000 people, including six hunter-gatherer groups who had lived isolated from the outside world for thousands of years.

The only way to get to the islands was by ferries but, as we later learnt, an estimated 94% of the jetties in the region were damaged.

That was also the reason why, on 26 December 2004, we never made it to Havelock. The jetty there was damaged and under water, we were told.

So the boat turned around and started on its return journey. For a while, there was speculation that we might not get clearance to dock at Port Blair for safety reasons and might have to spend the night at anchor.

This made the passengers – most of them tourists looking forward to sun and sand – anxious.

After several hours of bobbing along in rough seas, we returned to Port Blair. Because Phoenix Bay had been closed following the morning's damage, we were taken to Chatham, another harbour in Port Blair. The jetty where we were dropped had huge, gaping holes in places.

The signs of devastation were all around us as we headed home – buildings had turned into rubble, small upturned boats sat in the middle of the streets and roads had great gashes in them. Thousands of people had been turned homeless when the tidal wave flooded their homes in low-lying areas.

I met a traumatised nine-year-old girl whose house was filled with water and she told me she had nearly drowned. A woman told me she had lost her entire life's possessions in the blink of an eye.

Over the next three weeks, I reported extensively on the disaster and its effects on the population.

It was the first time a tsunami had wreaked such havoc in the Andaman and Nicobar Islands and the scale of the tragedy was overwhelming.

Salt water contaminated many sources of fresh water and destroyed large tracts of arable land. Getting vital supplies into the islands was tough with jetties unserviceable.

The authorities mounted a huge relief and rescue effort. The army, navy and air force were deployed, but it took days before they could get to all the islands.

Every day, navy and coast guard ships brought boatloads of people made homeless by the tsunami from other islands to Port Blair where schools and government buildings were turned into temporary shelters.

They brought stories of devastation in their home lands. Many told me they had escaped with nothing but the clothes on their backs.

One woman from Car Nicobar told me that when the earthquake struck, the ground started to spew foamy water at the same time as the waves came in from the sea.

She and hundreds of others from her village had waited for rescuers without food or water for 48 hours. She said it was a "miracle" that she and her 20-day-old baby had survived.

Port Blair was almost daily jolted by aftershocks, some of them strong enough to start rumours of fresh tsunamis, making scared people run to get to higher ground.

A few days later, the Indian military flew journalists to Car Nicobar, a flat fertile island known for its enchanting beaches and also home to a large Indian air force colony.

The killer tsunami had completely flattened the base. The water rose by 12 metres here and as most people slept, the ground was pulled away from under their feet. A hundred people died here. More than half were air force officers and their families.

We visited Malacca and Kaakan villages on the island which also bore the brunt of nature's fury, forcing residents to take shelter in tents along the road. Among them were families torn apart by the tidal wave.

A grief-stricken young couple told me they had managed to save their five-month-old baby, but their other children, aged seven and 12, were washed away.

Surrounded by coconut palms on all sides, every house had turned into rubble. Among the personal belongings strewn about were clothes, textbooks, a child's shoe and a music keyboard.

The only thing that stood - surprisingly intact - was a bust of the father of the Indian nation, Mahatma Gandhi, at a traffic roundabout.

A senior army officer told us his team had recovered seven bodies that day and we watched their mass cremation from a distance.

At the air force base, we watched as rescuers pulled a woman's body from the debris.

An official said that for every body found in Car Nicobar, several had been swept away by the waves without leaving a trace.

After all these years, I still sometimes think about the day I hopped on the ferry to go to Havelock.

I wonder what would have happened if the tremors had come a few minutes earlier.

And what would have happened if the wall of water had hit the shore while I waited on the jetty to board our ferry?

On Boxing Day, 2004, I had a close call. Thousands who perished were not so lucky.

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