Gerardo Nieto is fighting a losing battle to maintain his tour group's attention.
He's building towards the crux of a historical tale about Cartagena, an almost 500-year-old city on Colombia's Caribbean coast, but over near the stone wall that rings the old town, a couple of police officers have pulled aside a young man, ordered him to place his hands on his head, and begun emptying his pockets.
Nieto, our leader on a cycle tour, chuckles as he scraps the lecture and attempts to explain the present-day scene that's stolen our concentration.
Without shedding any light on what the police are looking for - one can't help assuming it's got something to do with a certain illicit white powder - he merely says the Government has been placing a lot of effort into improving security in the country, particularly in tourist hot spots such as Cartagena.
Colombia is desperately trying to shake off its reputation as a good place to go to get mugged or kidnapped.
It wasn't so long ago that it was known as one of the most dangerous countries in the world to visit. Nowadays, its tourism slogan is, "Colombia: the only risk is wanting to stay".
While that might be about as true as New Zealand's "100 per cent Pure" campaign - left-wing rebels and heavily armed criminal groups still operate in some areas - it has become a vastly safer place to visit than it was in the 1980s and 1990s, when powerful drug cartels held the country to ransom.
We'd arrived in Bogota, Colombia's mountain-ringed capital, a couple of days prior to the cycle tour.
The city sits at about 2600m above sea level and my temples are pounding from the altitude on our first morning in the country.
Not helping matters is a trip, by cable car, to the mountain-top sanctuary of Monserrate, at well over 3000m.
Though the church that crowns the mountain is a popular destination for Catholic pilgrims, especially on Sundays, the lookout also offers a sweeping view of Bogota for the less religiously inclined.
Below us, the concrete skyscrapers of the central business district reach for the clouds, surrounded by a sea of salmon-coloured rooftops stretching across the Andean basin the city occupies.
After descending from the heights of Monserrate we take a stroll through Bogota's La Candelaria area, a historic neighbourhood with narrow streets, 300-year-old houses and a square populated by so many pigeons I accidentally step on one unsuspecting bird.
The nearby Museo del Oro (Gold Museum) is a must for anyone interested in Colombia's pre-European history, with a huge display of the indigenous jewellery and other treasures that lured the Spanish to the region at the start of the 16th century.
Further north, Bogota's newer areas offer swanky malls and trendy bar and restaurant districts.
With a fast-growing economy, the Colombian Government is pouring billions of dollars into new infrastructure.
Later that day we're subjected to one of the side effects of that investment - Bogota's already congested traffic has been worsened by the construction of new roads.
One of the main thoroughfares of the central city has been pretty much reduced to a single lane while work is undertaken to widen it.
As our van crawls through the crush, commuters in packed buses, many of which resemble horizontal space rockets, are nodding off as they begin what must be a very long trip home.
At least the traffic provides time to spot some of Bogota's retail oddities, including a shop that specialises in TV remotes, with thousands of different models on display, and another that focuses solely on Jesus statues.
Escaping the city the next morning, we drive about 50km north-east through rolling farmland to the Laguna de Guatavita.
The lake, which sits within a crater, was sacred to the indigenous Muisca people, who threw gold trinkets and jewellery into its murky waters during religious ceremonies in pre-colonial times.
These rituals are thought to have given rise to the El Dorado legend - the mythical lost city of gold that captivated the imaginations of the Spanish conquistadors and other European explorers.
The lake might have been a destination for only the most intrepid adventurers 400 years ago, but the same can't be said today.
Arriving at the carpark, one of my companions expresses his disappointment at the sight of hundreds of Colombian school children, all dressed in navy blue tracksuits, preparing to make the short walk up the well-worn track that leads to the crater rim.
"If there's anything that takes the adventure out of travel, it's school kids," he complains.
Following a group of students, we soon reach the base of a deep chasm, dug by hand in the late 1500s when Antonio de Sepulveda, a wealthy Spanish merchant, attempted to drain the lake and bag its hidden treasures.
His efforts, like those of many others over the centuries that followed, yielded very little gold, and De Sepulveda died penniless.
From Guatavita we return to Bogota and catch a late-night flight north to Cartagena, where the tropical air feels pleasantly soggy following the sometimes chilly temperatures of the capital and its surrounding areas.
The coastal city on the southern edge of the Caribbean basin, about two hours' flying time south of Miami, hit the headlines around the globe in April after a group of Barack Obama's Secret Service agents, who'd flown to Cartagena ahead of the President to prepare for a political summit, got busted taking prostitutes back to their hotel.
Although there is a seedy side to the city, its colourful old town is a gem; a perfectly preserved, outdoor museum piece.
You can lose yourself, sometimes literally, in the maze of streets that weave between colourful facades, opening into leafy plazas where the locals gather to read newspapers and shoot the breeze.
Many of the buildings that once housed the Spanish colonial elite have been converted into boutique hotels, their inner courtyards now complete with swimming pools and restaurants.
During the colonial era, precious metals such as gold and silver, plundered by the Spaniards in the Latin American hinterland, were stored in Cartagena while awaiting shipment to Europe.
The great riches of the city led to it being ransacked on numerous occasions.
England's Sir Francis Drake occupied and partially destroyed the city in the late 16th century, after which Cartagena's forts and roughly 11km of walls were constructed.
In the absence of pirates, visitors can now sit atop the wall at the Cafe del Mar, sipping pina coladas as the sun sets over the Caribbean.
A good way to see the city is on Gerardo Nieto's cycle tour, which focuses on Cartagena's cinematic history.
According to Nieto, a native "Cartagenero" whose late father, Victor, founded the Cartagena Film Festival in 1960, more than 50 movies have been made in the city.
The most famous is probably Love in the Time of Cholera, the 2007 film based on the 1985 novel of the same name by Colombian author Gabriel Garcia Marquez, who cut his journalistic teeth in Cartagena while studying law at the local university.
The Nobel laureate still owns a house on the edge of the old town, the mystique of which is said to have influenced the writer, one of the best-known purveyors of the literary style known as magic realism.
Riding along the top of the northern wall at dusk, we reach Garcia Marquez's large, earthy-coloured home, which sits behind an imposing wall.
Nieto says the house is unpopular with some locals.
"People think it's ugly," he says.
Minutes later, after descending into the streets of the old town, Nieto's lecture on the history of Cartagena's theatre gets interrupted by that mysterious police search.
I'm expecting the cops to pull a few grams of cocaine, a gun or at least a knife out of the suspect's pockets.
Nothing illegal is found, however, and the young man is let go.
That kind of sums up my journey through Colombia; although I travelled to the country expecting at least some edginess and danger, I'm not confronted with any - even when venturing out alone. And as the journey ends I do fancy staying in Colombia. Maybe there's a bit of truth in that tourism slogan after all.
From its lush highlands to teeming cities and muggy Caribbean coast, Colombia is a vibrant and friendly places. Cartagena is one of those mysterious, intoxicating places where you can feel history in the air.
Getting there: LAN flies six times a week from Auckland to Santiago, and on to Bogota and Cartagena.
When to go: Colombia has two dry seasons, between December and March, and July and August, although rain is possible at any time of the year. Being a tropical country there is little variation in temperatures year round, with the highland areas generally cool and the low altitude regions hot.
* Christopher Adams travelled courtesy of LAN and Proexport Colombia.