My first night in Beirut was disrupted by gunfire and explosions. I had been on edge since arriving at the airport at dusk, and now, in the darkness of my hotel room, my instinct was to dive for cover under the bed. But that was precisely where the noise seemed to be coming from.

I flicked on the light and lay tensely, my heart thudding. When the cacophony of violence gave way to music, the truth dawned. My room in the Pavillion Hotel was located directly above a cinema. What I was hearing was not the resumption of the Lebanese civil war, but rather the Hollywood blockbuster Independence Day.

This was 1996, and I was making my first visit to Lebanon’s battle-scarred capital. The war had been over for five years, yet the rebuilding of the city had barely started.

The hotel was located on Hamra Street, once one of the chicest streets in the Middle East. The boutiques and wealthy shoppers had not returned. The street still appeared to be shell-shocked.

At the height of the conflict, Hamra Street had been one of the main arteries of Muslim West Beirut and had been a no-go area for Westerners. As I walked north toward the American University of Beirut, I passed the corners and curbsides from which British and American hostages had been abducted; some of them were held in dingy basements for more than five years.

There was evidence of the city’s trauma everywhere. Walls were pocked with bullet holes. Rusty cartridge cases littered every patch of waste ground. The Holiday Inn, once one of the region’s finest hotels, was a guttered, high-rise ruin.

But when I reached the Corniche, the road that sweeps along the Mediterranean seafront, I was able to imagine Beirut’s glamorous past. Throughout the 1950s and ’60s, the city had been a favorite of the international jet set.

That golden era was a faded memory, but here there were echoes of the good times. Couples strolled along the promenade hand-in-hand. Children on in-line skates weaved among the pedestrians. Men sat fishing from the seawall.

At the bombed-out St. George Yacht Club, an impromptu café had been established in the shadow of the building’s soot-blackened façade. Over a round of beers I chatted with a young Lebanese couple.

“When the war started, if we heard mortars or gunfire in the distant southern suburbs, we would stay awake all night, ”one of them told me. “Then we got used to it. We would only be sleepless when the fighting reached our neighboring district. Then we got used to that, and we would only worry if the fighting was in the next street. By the end of the war, the mortars had to fall on our own doorstep to make us frightened. That is how it was. We became numb.”

Later I met up with an old school friend, a relative of the former Lebanese president, Amine Gemayel. He spread a map of Beirut on our restaurant table and explained the complex patchwork of communities that make up the city.

“Here we have Shiite Muslims. Here, Sunni Muslims. In this area you find the Druze sect. This district is home to the Armenians. Over here is where my people congregate, the Maronite Christians. Down here are the Palestinian refugee camps.”

“I’m beginning to understand,” I said.

My friend chuckled wryly. “That is just the surface. Within the communities there are clans and families who have their own alliances and enmities, often going back centuries. In Lebanon, it is not always easy to know who is your friend and who is not.”

Beirut’s tangled demography is the result of its strategic position on the shore of the eastern Mediterranean. It has long served as a waypoint between Europe, Asia and Africa. The simmering tensions reach back to the very beginnings of civilization.

When I returned in late 2004, the city had been transformed. The rubble wasteland of downtown Beirut had given way to gleaming office blocks and leafy squares. The extremes of Lebanese society were starkly on view. From my hotel room I could see local women sunning themselves in bikinis by the pool, while on the sidewalk immediately beside the hotel it was common to see other women concealed head to toe in burqas.

Religious conservatism and Western decadence, poverty and wealth, coexisted uneasily. These fissures lay ominously beneath the surface of the rebuilt city, threatening new tremors and quakes. I began to think of Beirut as the San Andreas Fault of modern civilization.

Just as the periodic violence of a seismic fault can give rise to dramatically beautiful scenery, so the simmering tensions of Beirut have helped shape a city that is vibrant and thrilling. There is nowhere else in the world quite like it.

I enjoyed fine museums and galleries during the day, rubbed shoulders with young party-goers at night, and time and again returned to the Corniche to stroll with an everchanging cross-section of local society.

Gradually I dropped my guard and accepted the new Beirut at face value. I was not the first to make such a misjudgment. Sitting one afternoon at the bar of the refurbished St. George Yacht Club, I wondered if this really was the start of an everlasting peace.

Eight weeks later, on the road immediately outside the club, a huge bomb destroyed a motorcade, killing the man who had done much to rebuild Beirut, former Prime Minister Rafik Hariri. The following year, in response to missile attacks mounted by Hezbollah from Lebanese territory, Israeli jets bombarded Beirut, shattering much of the restored infrastructure.

As always, the city dusted itself off, cleared up the debris and set about repairing the damage. Confronted by the enduring divisions and the recurring bouts of bloodshed, visitors to Beirut could easily regard this city as a microcosm of the world and find in it little hope for the future.

But on the afternoon in December 2004 when I flew out, I gazed down at the city, which nestled between the sparkling sea and snow-draped mountains, and saw it as a thriving monument to human resilience.