Rumbling along a dirt path in a brightly painted cart pulled along by two oxen, I feel like I've been put in a time machine and pitched up in a time before cars, air conditioning and other modern conveniences. The sun is beating down on the back of my neck and, aside from the buzz and crackle of insects, it's almost completely silent.

We overtake another cart, this time not carrying a sweaty journalist but a towering pile of woody stems: freshly harvested sugar cane, which is destined to become Ron Abuelo, Panama's oldest and best-known rum. It's distilled here at Hacienda San Isidro in the Las Cabras area, a three-and-a-half-hour drive from Panama City, Panama.

We pass underneath a picturesque arch, the path becomes a paved road, and my old-world reverie begins to fade as we come to rest outside a modern building overlooking the fields.

I pause to absorb the romance of the scene: fuchsia-coloured bougainvillea peeks out from every corner; palm trees gently fan the blue sky; and several of the brightly painted carts dot the landscape, manned by men wearing the now-familiar panama hat. Behind me are 11 wood-fronted bodegas; silent, reverential halls filled with wooden barrels of rum that are quietly and purposefully lying in wait until they reach perfect maturity.

They hand-harvest the cane before distilling and ageing the liquid on the estate

This is what makes Ron Abuelo so special: its cache of oak-aged rums, ranging from the seven-year-old to the centurian, which is made up of rums aged for a total of 100 years altogether. Abuelo means 'grandfather' in Spanish: a nod to the brand's history as Panama's oldest rum producer.

The story began in 1908, when Spanish immigrant Don José Varela Blanco arrived in Pesé – a small town in Las Cabras, near to where the distillery is located. There he established the country's first sugar mill, and by 1936, he and his three sons began distilling alcohol from freshly pressed sugarcane juice.

Today, the Varela family – third-generation descendants of Don José – continues to distil spirits from nearly 3,000 acres of estate-owned crops, one of the few rum brands in the world to do so. They control 100% of the production process, hand-harvesting the cane before distilling and ageing the liquid on the estate. The company's development goes in hand in hand with Panama's, so much so that Juan Carlos Varela became president in 2014.

Politics aside, it's the distilling process that I'm here to see. It's February, right in the middle of the sugarcane harvest, which means the processing plant and its employees are working 24 hours a day bringing the cane to be crushed. The fibrous stems are mashed, a machine extracts the sugar cane juice, and the crushed pulp waste is burned to generate power to crush the cane. Aside from obvious technological developments, things have been this way for almost a century, since Don José first embarked on his mission. The thinking is clear: why change the very things that made it so special in the first place?

While Caribbean countries tend to have the monopoly on rum in the UK, there's a reason why Panamanian rums deserve to be recognised. Panama, long and narrow in shape, has distinct weather patterns, particularly around Pesé, which is located in a fertile valley in the Azuero peninsula, giving the rum a unique terroir.

What's really significant is that the area lacks summer rain (a phenomenon called arco seco, or dry arch), and it boasts both Caribbean heat and air from the Pacific Ocean, so it has a unique microclimate of temperature and humidity. This is obviously important because it results in an abundance of sugar cane, but also because it has a distinctive effect on the aging process.

Ron Abuelo ages its rums in American white oak barrels, starting with the Anejo, a delicately spiced spirit that's ideal for cocktails. Next up is the deeper, more caramel-flavoured 7 Anos, aged for seven years in oak barrels.

The taste is buttery and rich, with notes of vanilla and honey

The Anejo 12 years is where things start to get interesting. It's Abuelo's flagship rum, designed to truly reflect the brand's precise production process and love of tradition. And it shows: the liquid is smooth and complex – ideal for sipping, like a whisky or cognac.

Finally, there's the Centuria, a limited-edition spirit that was initially produced to celebrate 100 years of rum production, and the Varela family opened up their private stock – featuring rums that have been aged for more than 30 years – in order to make it. A unique solera system is used to preserve the liquid's character over such a lengthy period, especially given that it's being produced in such small quantities.

The taste is phenomenal: buttery and rich, with notes of vanilla and honey – it's my favourite from the Ron Abuelo stable.

With such a complex range of flavours, it's unsurprising that Ron Abuelo has a loyal following in London bars. Chris Tanner, bar manager at The Vaults, Soho, particularly likes the seven-year-old rum. "I use it in classic cocktails like an old fashioned or a manhatttan. The sweetness and age of Ron Abuelo's rum mean you can swap it for whiskey and make these robust drinks more approachable."

This versatility and finishing process is Ron Abuelo's hallmark, which it has recently applied to a new collection of three rums finished in a different casks: oloroso sherry, tawny port or cognac. Each of these serves is delicious, imbued with a unique flavour.

As you can probably imagine, I become very well acquainted with the Ron Abuelo portfolio during my stay in the country. Each of the rums is sophisticated and refined; a perfect match for the elegant surrounds of Panama City's crumbling Casco Viejo quarter, where cool tapas restaurants occupy vine-covered ruins and young people flock to buzzy rooftop bars in search of a breeze. It's a melting pot of old-world colonial charm and modern sensibilities, with an irresistibly unique character – much like its favourite rum.

ronabuelopanama.com