Making a stranger cry in a crowded cafe in Reykjavik wasn't exactly what we had signed up for. But there we were, awkwardly clutching our steaming lattes as a young woman quietly wept in front of us. While we had never met her in person, we’d tracked her down using Facebook and arranged to meet while we were in town. The sole purpose of this encounter was to give her something that we had been carrying around the world with us for more than three years: a postcard.

This meeting had been a long time in the making. When my husband and I had first started dating, he would regale me with tales of a 300-year-old whisky-cask-turned-makeshift-post-office in the Galapagos Islands, 973km off the coast of Ecuador. The empty cask had been placed on Floreana Island in 1793, when whalers and sailors frequented the remote archipelago to restock on fresh water and giant tortoise meat. Since the seamen could be on the water for years at a time, they had to devise a clever way to communicate with beloveds at home – a tradition that continues to this day.

Before departing the islands, the forlorn seamen would place letters in the cask, addressed to friends and family all over the world. In return, they would search the barrel for envelopes addressed to their future ports of call, taking those that matched their onward destinations. When they arrived in a city where a letter was addressed, they would hand-deliver the letter to the recipient.

I envisioned young men composing letters of love and passion to their distant sweethearts back home; or jotting down appeals of forgiveness to their parents, apologising for their indefinite absence while beguiling them with exotic tales from sea.

I was enamoured by the fact that these men would have had little in common. Passing through the Galapagos, hailing from different nations and speaking different languages – their only bonds might have been a love of the sea and the admirable act of delivering the letters for their seafaring brethren.

Captivated by the history of the barrel, my husband and I decided we would venture to the Galapagos, scoop up a handful of letters addressed to all corners of the globe – and hand-deliver each and every one of them.

We set out for the islands in September 2011. Getting there was a feat in and of itself, as we not only secured the last two seats on a flight out of Ecuador, but also navigated the murky process of finding a Galapagos cruise itinerary that included both the mandatory certified naturalist guide and a guaranteed stop on Floreana island. We decided on a small chartered boat with a dozen or so berths.

Our first three days in the Galapagos were spent exploring the islands of Isabela and Santa Cruz: snorkelling with frisky sea lions, hopscotching over menacing-looking land iguanas, and spying on blue-footed boobies and red-chested frigate birds. And while we enjoyed being immersed in the archipelago’s unique flora and fauna, we often found ourselves distracted by our imminent arrival in Floreana.

In the heat of the afternoon on our fourth day, we motored into Post Office Bay in a tiny dingy, welcomed by the now-familiar, putrid stench of sunbathing sea lions. My sandal-clad feet sunk into the soft sand as we carefully disembarked from the inflatable raft. The majority of our companions were too occupied with a mother sea lion and her new pup to truly appreciate the hallowed grounds on which we were walking. All I could think about was opening the mailbox and finding piles of ancient letters, some hundreds of years old, still waiting to be delivered to those dearly beloveds across the globe.

We stumbled up the pathway that led to the barrel, anticipation gathering in my chest as we rounded the final rocky corner. Expecting to see a large whisky cask boldly welcoming us to our destiny, we instead found a tiny barrel that resembled more of a birdhouse than a mailbox. It was fastened out of driftwood and was held together with rusty nails and bumper stickers. My romanticised visions of weathered envelopes filled with confessions of love diminished when we opened the barrel to reveal an enormous pile of Galapagos-themed postcards – giant tortoises, dancing albatrosses and marine iguanas gracing the front of almost every one.

It also appeared that my husband and I were the only ones who had known about barrel’s legend before arriving. A few nights prior, I’d thoughtfully selected the lucky future recipients of my handwritten letters, taking time to prepare the dialogue within and carefully writing with the best penmanship I could muster. My fellow visitors weren't as prepared, hastily purchasing a few postcards from our guide and scribbling a quick note to whoever's address they had memorised by heart.

Not easily discouraged in our hunt for the magic and history of the post barrel, we began sorting through the piles of postcards. Amid the throngs of "wish you were heres" and inappropriate blue-footed booby jokes, we managed to find a handful of cards that appeared to hold messages of substance. A few were sent to loved ones that couldn’t make the trip, describing in intricate detail the exotic colours of marine iguanas and the paralysing fear of spotting a hammerhead shark while snorkelling. Some were letters of admiration, wishing the recipients well and thanking them for being a presence in the writer’s lives. There were cards written in English and some in languages we couldn’t decipher, but all were addressed to countries we either wanted to go to or knew we would be visiting in the future. We left the island with 22 postcards in all.

Fast forward three years and 17 countries. Halfway through our stack of postcards, we found ourselves in Iceland. We had just revealed the missive when tears started forming in our new friend's eyes. My husband and I shared an uneasy glance, as we weren’t sure what her next reaction would be. Her tears quickly turned to stifled laughter. Half sobbing, half smiling, she explained that she had written the postcard to herself and our lack of comprehension of the Icelandic language resulted in us missing a key element scribbled on the top right-hand side of the postcard: that it should be left in the barrel until she could return to get it.

However, she then told us that her life had drastically changed from when she was there last, and the delivery of her postcard could not have come at a better time, since it was unlikely that she’d ever return to the Galapagos. Her self-written postcard reminded her of how far she’d come since her visit four years prior, and of all of the positive changes that had occurred. We spent more than an hour in the tiny cafe, lingering over our lukewarm lattes as we bonded over our shared love of adventure, the story of the post barrel and the future.

Upon saying our goodbyes, our new friend joked that if we had delivered the postcard any sooner, it might not have had the same impact as it did on that day. And I realised: when we’d started this adventure, the allure was the destinations. But what’s been truly been remarkable is the people and the stories that we’ve encountered along the way. We might not be the quickest form of mail delivery, but we somehow manage to arrive at just the right time.

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