Missing Madeleine

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PRAIA DA LUZ, PORTUGAL - Portugal, the coastal edge of Europe, has always been about the sea.

Its great explorers sailed off into the mostly unknown centuries ago and brought back unimagined wealth to the tiny kingdom.

But history eclipsed Portugal. The colonies and trade routes lost to greater powers.

It was up to the humble sardine to pay the bills.

But in the last 40 years the sea has given the Portuguese its best catch since the glory days of Magellan: the British tourist.

It's the blustery off season now but in the spring and summer a million tourists every year -- about half of them British -- are disgorged onto the warm beaches, all inclusive resorts and villas, and cheap and cheerful pubs more English than the queen. The southern coastline the Brits call the Algarve has the reputation of being sedate, family-oriented, and safe.

After a gloomy English winter and dank spring, the prospect of a vacation week in sunny Portugal must have been especially appealing to the McCann family living in central England.

Gerry and Kate McCann are both doctors. Their daughter Madeleine three, about to turn four. The twins, Sean and Amelie, are two.

The resort they'd selected sounded ideal for a young family. The ocean club overlooks one of the best beaches on the Algarve -- Praia da Luz.

Praia da Luz is an old fishing port that has really become a tourist destination.

Richard Gaisford is the chief correspondent for one of Britain’s morning news programs. He spent weeks last summer reporting from the Portuguese village.

Richard Gaisford: It's a very warm welcoming friendly place.

>getCSS("3088867")</SCRIPT> ></SCRIPT> Video <INPUT class="mbox w77" onmouseover="swapbtn(this, 1)" title=Launch onclick=" javascript:msnvBut(event);vPlayer('21790617','ae4fb2c0-5171-4940-8a23-23cff03a091a'); " onmouseout="swapbtn(this, 0)" type=button value=Launch>   Why was Madeleine unattended? John McCann says his brother Gerry and Kate McCann left their children unattended because they were in a safe, home-like environment. Dateline NBC

And it was a place the McCanns knew well. They'd been to the resort before.

The main attraction for the young parents was the resort's "award-winning childcare."

Richard Gaisford: They have qualified childcare looking after the kids during the day. That way the kids have fun, the parents get to relax and everyone is happy.

They were taking their holiday with friends, other couples in their doctor circle.

In a cell phone video of Madeleine, she’s  hand in hand with one of her friends as they board the plane to Portugal.

She was the child they'd long been waiting for.

Gerry and Kate met while training to be doctors -- two motivated young achievers from working class Catholic backgrounds. Kate was from Liverpool. Gerry from gritty Glasgow.

The couple’s often told story was love at first sight, at least from Gerry’s side...

The cardiologist and soccer-crazed ball player-- falling head over heels for the pretty, top-of-her class blonde.

But as much as the newly married couple wanted children they had trouble conceiving. After four years of marriage and in vitro treatments, Kate gave birth to Madeleine in 2003.

A beautiful wee girl. That’s how John McCann, Gerry’s older brother, thinks of her.

John McCann: She loves parties. She loves, you know, groups of-- her friends. She's always been a wee effervescent thing.

FindMadeleine.com Could this be Madeleine's abductor? This is an investigators' sketch of a man in a droopy moustache seen in Praia de Luz at the time Madeleine disappeared.

The family had recently settled in Rothley, England, about 100 miles north of London.

That's where the twins were born -- again conceived in vitro.

Life inside their upper-middle class home is described as a happy balancing act between family and careers.

John McCann: So there's a big focus of getting the work done. Getting the work out of the way. And getting on with looking after the kids.

So the young family -- Kate and Gerry both are in their late-30's -- had reason to be happy last April as they rode the shuttle bus to their sunny Algarve getaway.

John McCann: They'd been working very hard and they were really looking forward to meeting up with their friends who had kids of the same age as theirs. So you know, it was going to be a win-win-win for everybody.

The ocean club resort turned out to be as good as advertised.

The McCanns settled into a ground level apartment with two bedrooms a kitchen and a patio. The only downside, perhaps: it's an end unit and some of the windows face onto the village street.

There were two swimming pools and two restaurants.

One of them, the tapas bar, had a pleasant open air patio where guests could dine under the stars.

By May 3, 2007, the McCanns have been soaking up the sun and lush evenings for a few days.

Richard Gaisford: The family was settled, they were relaxed, they were into their holiday routine.

At 2:29pm Madeleine has just returned from a family picnic by the beach when this snapshot is taken of her by the pool.

She is clearly an adorable child. Do her appealing looks partly explain why this is the last photo known to have been taken of her?

By 10:00pm, she'd vanished. Gone as though she'd stepped off the face of the earth.

A holiday getaway abruptly becomes a criminal investigation. Carefree, happy snaps now part of a critical timeline.