In his epic ‘The History of the Decline and Fall of the Roman Empire’ Gibbon mentioned that Constantine founded this city at the confluence of Europe and Asia as "an eternal monument of the glories of his reign."

For centuries, this city was known as Constantinople. Now it is called Istanbul -- the only city that lies on two continents, an incomparable fusion of East and West.

Istanbul is the city to revisit the mysteries of the Roman era, the glories of the Ottoman times, to gain an insight into the emergence of a new, modern Turkey, a sleeping giant that is beginning to throw its weight around as a major regional player. It is where a multitude of tourists pour in, where the results of years of impressive Turkish leadership are on increasing display, where business thrives in the shadows of elegant mosques that attract the faithful five times a day.

I first visited Istanbul in April 2006 for a conference on disaster management. With two full days taken up by the conference, I was left with only a few hours before my flight on the third day to see what Istanbul was all about. Those few hours allowed a quick visit to the impressive Topkapi Palace and a leisurely stroll a couple of kilometres up to Kapali Charsi -- the famous Grand Bazaar -- dodging the myriad trams, buying a couple of Istanbul pictures, savouring the unforgettable tastes of hot, mouth-watering roasted chestnuts.

I returned to Istanbul at the end of 2010, this time to see the city at leisure. During Eid ul Azha holidays in mid-November, I started driving with my family and visiting parents, from Athens (where I’ve been living for the past few years), some 1100 kilometres to Istanbul to further explore its sights and sounds.

Istanbul was its usual self -- welcoming, imposing, awe-inspiring, bustling. Eid festivities added to the colour. People elbowed their way through the shopping areas, serpentine queues snaked into the tourist attractions, muezzins called for prayers from mosques that dotted the city on either side of the Bosphorus. Life in Istanbul, described in such vivid detail by Nobel-prize winning Orhan Pamuk, pulsated night and day.

In the heart of the old city, six imposing minarets rise unceasingly into the late November sky. The Sultan Ahmet Mosque, better known perhaps as the Blue Mosque for its blue tiles that adorn the interior walls, is the signature sight of this city of endless charms. Rows of fountains, neatly placed in elegant, lush gardens, spout frothy water. On Eid day itself, thousands of smartly dressed worshippers, men and women, young and old, thronged the Blue Mosque, and other mosques throughout the city, for prayers in an impressive and inspiring show of faith, brotherhood and harmony.

Across the gardens rises the imposing facade of Hagia Sophia, the epitome of Byzantine architecture and for nearly a thousand years the largest cathedral in the world as well as the seat of the Patriarch of Constantinople. Now it is neither a church nor a mosque. Yet, Hagia Sophia retains its elegance, its vast, ornamentally-decorated main hall welcoming people of all faiths and backgrounds. As in the Blue Mosque, names of Prophet Muhammad (PBUH) and the four Caliphs prominently adorn its upper reaches, inscribed on circular-framed medallions hanging from sturdy columns. On its upper gallery, a marble plaque marks the grave of Henricus Dandolo Doge of Venice, commander of the Latin armies that invaded Constantinople in the Fourth Crusade. He is said to have died during the expedition and buried in Hagia Sophia.

In its shadows, rows of restaurants serve their versions of Turkish delights as jam-packed trams trundle up and down past endless boutique shops and international fast food outlets. A couple of kilometres, beyond to the west, lies the Grand Bazaar; its maze of criss-crossing covered streets brimming with unknown secrets to be explored -- jewellery, pottery, spices, crystals, carpets, lamps and linen et al overflow from thousands of shops on to the brightly lit alleys. We spent an hour at the Grand Bazaar was too little, especially since my mother and wife had heard so much of Turkish silver jewellery and crystal pieces.

East of Hagia Sophia, the road slopes down past the entrance to the extensive complex of the Topkapi Palace, for centuries home to the Ottoman sultans and a perfect example of Ottoman architecture. Now converted into a museum, it is a proud repository of the "sacred trusts" -- items belonging to Prophet Muhammad (PBUH), his companions and other prophets, as well as thrones, porcelain, jewellery, weapons, carriages and other paraphernalia from the Ottoman times.

Some inner terraces afford stunning panoramic views of the Bosphorus and the Sea of Marmara, the rolling hills on the Asian side of the city beyond the choppy waters traversed by innumerable vessels. Out in the distance is the glistening Bosphorus bridge, suspended high above the water and bringing the two continents together.

In the mid-19th century the Ottomans abandoned the Topkapi Palace for the modern and luxurious, European-style Dolmabahce Palace, still the largest palace in Turkey. The extravagant palace, where Mustafa Kemal Ataturk also breathed his last, lies on the banks of the Bosphorus just south of Taksim Square. The extravagant gold-plated ceilings and railings, oriental carpets, huge chandeliers, impressive paintings and beautiful crystal leave thousands of visitors awestruck on a daily basis.

Modern commerce continues unabated outside, huge oil tankers chug through the Bosphorus transporting oil from the Black Sea ports to the world beyond, ubiquitous vessels of various shapes and sizes transport men and material. On the other side, high-rise buildings, home to financial institutions and multinationals, peep in from behind the tall trees -- a continuing reminder and proof of Turkey’s growing economic power.

The modern funicular railway plies between the shores of Bosphorus, close to the Dolmabahce Palace, and Taksim Square, the heart of modern Istanbul, with its volatile and colourful mix of demonstrators, shopkeepers, policemen, tourists and youngsters. Foreign fast food outlets, interspersed with local eateries, line the entrance to the bustling Istiklal Street that meanders through the centre of Istanbul for almost three kilometres up to the Galata Tower.

Throughout its length exquisite boutiques, cinemas, cafes, bookstores and theatres conveniently overshadow a sprinkling of majestic structures from the late Ottoman period. Towards the end, dark, narrow streets and alleys wind down towards the Bosphorus under overhanging balconies jutting from dark, dilapidated multi-storey houses.

Before leaving Athens my father expressed his desire to visit the tomb of Hazrat Abu Ayub Ansari, the companion of Prophet Muhammad. And so I was not leaving Istanbul before locating and visiting the site. Lying in an austere setting next to the Eyup Sultan Mosque, the first mosque constructed by the Ottomans following their conquest of Constantinople in 1453, with its large shady courtyard in a non-descript part of the city, the tomb is a far cry from the Ottoman glamour and Turkish glitter. Yet, it attracts hundreds of visitors daily. Outside, on the far side of a lovely fountain, rows of shops sell copies of Holy Quran, Turkish caps and rosaries.

On our last night in Istanbul, the night before Eid ul Azha, we returned to the old city. The Blue Mosque, its six minarets and myriad domes beautifully illuminated in mellow shades of blue and yellow, dazzled in all its majesty. Nearby, in the vicinity of Hagia Sophia, restaurants did brisk business. We dined on traditional Turkish food -- mousaka, stuffed vegetables, and rice with meat. Mustafa, the bespectacled chef, neatly dressed in all white, promised to serve us even better food on the Eid day. But by the same time the next day we were in Thessaloniki, hundreds of miles away, en route to Athens.