The taxi from our modern hotel just around the corner from one of Lisbon‘s wide boulevards, the Avenida Liberdade, to the historic Bairro Alto district takes only a few minutes but is a step back in time.

The streets narrow until we crawl in first gear up curving, cobblestoned lanes with only just enough room for the driver to manoeuvre. Opened doors in brightly plastered walls reveal glimpses of bars, clubs, pubs and boutiques. It‘s Friday and we‘re late for dinner, but this is Lisbon and the night has barely begun.

We asked the driver to take us to a restaurant where they feature fado, music which expresses the heart of the Portuguese soul, and he takes us to A Severa, dawdling for a moment to ensure he picks up his "commission" from the maitre d‘. Once inside, we notice its suitably rustic combination of brick and plaster.

To be successful a fado singer must possess saudade, a Portuguese word meaning longing, or nostalgia.

One singer, Natalia Escoval, holds us transfixed as she sings in her torn, piercing voice accompanied by three guitarists, including a bass guitar, or viola. "I try to put music to poetry," she tells me in between sets. "I sing about life, death and the life God gave us."

The driver has chosen well, as the audience is obviously mostly Portuguese, because her next song, a more upbeat number, has them singing along with gusto. The food was fine, but the gypsy couple was geriatric and be wary of the antipasto platter, which is not on the menu and is overpriced.

Back out on the street, the pleasant autumn weather has attracted tens of thousands of revellers to the Barrio Alto. I join the throng in the tiny lanes, buy myself a drink and stroll over the polished taupe and blue cobblestones, wandering into whatever bar has appeal. There is more fado and just about every other kind of music, and the television is almost always showing football, because the Portuguese are crazy about the sport.

You can buy a custard tart from a hundred places around Lisbon, or from anywhere around the world for that matter, but none will ever match the pastel de belem made at a Lisbon landmark, the Antiga Confeitaria de Belem. Only three people know the secret recipe, and every morning two of them disappear out the back to oversee production of some 100,000 tarts a week. They disappear like hot cakes, with locals and tourists alike queuing impatiently.

Suitably fortified, I walk past the lavishly decorated high walls of the Mosteiro dos Jeronimos, or Jeronimos Monastery to the ornate entrance. Constructed of a light golden limestone between 1502 and 1552, the monastery commemorates the Portuguese explorer Vasco da Gama‘s successful return from India and was funded by a spice tax. He is buried here in a stone tomb, along with various members of the Portuguese royal family, among the soaring arches and inspiring high altar of a Gothic masterpiece.

In the same complex, a 55 square metre courtyard with two­storey cloisters is a perfect site of repose, with broad arcades overlooking an immaculate swath of lawn.

Most of us have heard of Vasco da Gama, but a look inside the Museo de la Marina, or Maritime Museum, which occupies an annex to the monastery, helps reveal Portugal‘s former dominance of the world抯 oceans.

Full­length portraits and statues honour not only admirals and captains but also the navigators who created the charts and set the courses for the great merchant shipping fleet to follow.

There are models of ships and old uniforms, and a modern annex yields the unexpected sight of rows of deeply carved and gilded royal barges which were propelled by scores of ornately dressed rowers.

In the central city area known as Baixa I spend a couple of hours window shopping and admiring Lisbon‘s elegantly dressed office workers while enjoying the local specialty of bacalhau, or salted cod, with a salad, washed down with the Portuguese Sagres lager.

At the end of one lane, I spot the iron lift known as the Santa Justa Elevator, built by a pupil of Gustave Eiffel, and take the 45 metre­high ride for an imposing view of the city.

The unmistakeable clank of an old tram catches my attention and I line up at the local stop. I let the sleek, enclosed modern trams go by and instead climb aboard a wooden old­timer with open windows. Soon we are twisting around the narrow streets of another historic quarter, the Alfama. Builders flatten the rear view mirrors on their trucks so we can pass. Old shops and older churches grab our attention and many buildings have colourful glazed tiles on their exterior.

The Castelo de Sao Jorge, or St George‘s Castle, the focal point of the Alfama, sits on the peak of the highest of Lisbon‘s seven hills. Its oldest parts date to over a century before the birth of Christ and in its time it has been a Roman stronghold, a Moorish royal residence and a palace for the Portuguese royal family.

Most of the castle was destroyed over the years, especially in the Great Earthquake of 1755, which devastated Lisbon and was followed by several tsunami and raging fires.

King Joseph I, keen to have a new city, commissioned the expansive squares, avenues and wide streets which make the city‘s downtown so liveable today. When the prime minister of the time, the Marquis of Pombal, was asked about the need for such streets, he is said to have replied: "One day they will be small."

Today the castle complex consists of the castle proper, known as the castelejo, towers, ramparts, gardens and a terraced square. Steep cliffs provided protection from invaders on one side, a moat, now drained, and a bridge with heavy gates on the other.

It is now an oasis of peace, but as I file through the main gate a statue of King Afonso Henriques and several cannons act as reminders of the castle‘s original purpose.

I climb the towers and walk along the ramparts to see panoramic views of the city and the wide avenues of Baixa as envisioned by King Joseph.

It is easy to follow the sweeping curve of the River Tagus and the two national monuments which commemorate Portugal‘s Age of Discovery in the 15th and 16th centuries.

The older is the Torre de Belem, a fortress built in 1515 to guard the entrance to Belem Harbour. It was the starting point for many historic voyages and for many sailors it was the last sight of their homeland.

A few hundred metres up­river is the Padrao dos Descobrimentos, a 52 metre­high monument completed in 1960. Shaped like a ship‘s prow, it features richly carved figures of great people of the era. The best known are Vasco da Gama, Henry the Navigator and Ferdinand Magellan, but other navigators, along with painters, writers, captains and mathematicians, also have their place in the sun.

As the train from downtown Lisbon to the world heritage site of Sintra gathers speed, we climb past drab suburban apartments and head into an enchanting, fairy­tale landscape beloved by royalty and the rich for its location, climate and romantic atmosphere. A weekend is really needed to take in all the palaces and other attractions, but I only have an afternoon.

I crowd onto the local bus and head up to the solid defences of the ominous Castelo dos Mouros, or Castle of the Moors, which overlooks Sintra.

The earliest parts date back about the ninth century. Today it is more like a story­book version of the Middle Ages with its towers, steep stone walls and the remains of a Romanesque church.

About half way back down the hill the mood changes to pure Romanticsm at the Quinta da Regaleira. Built between 1898 and 1912, this world heritage site is Wagnerian in its massive scale, drama and emotional intensity.

The Portuguese philanthropist and collector Carvalho Monteiro, who inherited a huge family fortune, dedicated himself to transforming the four­hectare summer retreat into an exuberant mix of Gothic, Renaissance and other architectural styles combined with heavy symbolism.

The main house is sumptuously decorated in wood and stone, with paintings and art works at every turn. Turrets and terraces look out over the magical and mysterious garden, said to be no less than a quest for paradise.

Underground walkways, tunnels, snaking paths, an ornate chapel and other outbuildings add to the sense of wonder.

It is something of a relief to be back in the central square of Sintra, which is dominated by the two extraordinary looking conical, or should that be comical, kitchen chimneys of the Palais National de Sintra.

A focal point of Sintra‘s cultural landscape and another world heritage site, it was a royal residence from the early 15th century until Portugal became a republic in 1910.

Of special note are the long Swans Hall, where each wooden ceiling panel has a painting of a swan, and the coloured, glazed tiles from the 15th and 16th centuries in the Royal Chapel, the Coat of Arms Room and various halls and patios.

On my final day in Lisbon I make time for lunch and my last of many pastel belems at Cafe Nicola, a superb example of art deco and totally authentic.

A few hours later, I board a small, luxurious cruise ship for a 10­day voyage across the Atlantic Ocean to Puerto Rico.

As with those sailors of the distant past, my last sight of Lisbon as we head to sea is the Torre de Belem. I gain a sense of saudade, a feeling of nostalgic longing for a place I have become fond of, with the knowledge that I may never return.