Shona looks stunned. "Nooooo!" she calls into the cold night. "You can't go home! It's going to be a good craic, it really is."
Her friend May is wavering, you can see it. The smart part of her wants to call it a night right now, but the three-pints-of-Guinness-already part of her is hungry for more. She stops in the street to consider the offer.
"Oh, all right. But just for one more drink," May says.
Famous last words. Especially around here. Shona laughs, then she and May link arms and away we go into the night, in search of the craic, of the next pub with a band and a barman and a steady supply of thick, black beer.
You were expecting a column about an island, right? Well, this is it. My favourite island, too: Ireland.
Ireland possesses all of the basic tenants to be defined as an island. It's girt entirely by sea, it's ringed with beaches, and its inhabitants seem to have a mindset of their own.
But it's not the stereotypical version of an island. There's no sun, for starters. People do surf here, but those people are clearly mad.
They might occasionally wear boardshorts, too, but that's when there's a tropical-theme party at the local nightclub.
They don't say things such as "bula" or "kia ora", but they do have their own special way of welcoming strangers with open arms.
This is my kind of island holiday. It's a personal thing. Some people dream of palm trees and infinity pools. I dream of pints of Guinness and games of pool.
That's why I've skipped the south Pacific this time in favour of coming to Derry for my holiday. Even the locals think I'm crazy.
The taxi driver from the airport laughs as I look outside the window at the drizzle enveloping Derry's green hills.
"Don't worry," he assures me, "it only rains in Derry twice a week. Once for three days, and once for four days. Ha!"
I'm not bothered, though, because this, quite clearly, is pub weather. And if there's one thing they do well on this island of mine, it's pubs. And music. And beer. And craic.
I spend a few hours walking Derry's city walls under the protection of an umbrella before the sun goes down (probably, as I can't see it) and the city really starts to hit its stride. As Derry is Britain's City of Culture this year, I'm heading to a concert first, a showcase of local artists held in an old church.
That's where I meet Shona, who's sitting next to me and decides to strike up a conversation, as people in these parts are wont to do. "You from around here?" she ventures by way of an opener. I am not.
Shona is, however - she presents the arts program on the local radio station. She seems to know just about everyone in Derry too, so I'm sure she already knew the answer to her first question. As the concert draws to a close she gives me a smile. "Yer wantin' to come for a pint then? It'll be good craic."
So we wander onto the street and meet her friend May, who gets two blocks before deciding she'd be better off going home. Shona soon talks her out of that nonsense, though, and on we go into the night.
Soon we've picked up more company in the form of Darren, Shona's boyfriend. He's a writer for the local paper. The four of us pass through a gate in the city walls and walk into Mason's, a pub that barely has space for four more bodies to squeeze inside it.
There's a band playing at a level that would drown out conversation in any other country where they weren't so passionate about conversation. There's a bar, doing an incredible trade in pints of Guinness. There's a dance floor filled with swaying bodies and raised arms. It's raucous. It's fun.
This is the sort of thing that happens on my favourite island: nights out with people who were complete strangers a few hours ago; live music in centuries-old buildings; chat about arts and music and writers and history.
As the evening draws to a close, the band finishes and the human contents of the pub are poured out onto the street, left to go their separate ways like the raindrops hitting the cobbles below us.
It's time to say goodbye to my new friends.
"Wait a minute," Darren slurs, grinning, not wanting the fun to end. "Nobody goes home until I hear five cliches."
Shona rolls her eyes. "I avoid cliches like the plague."
"Ha!" Darren laughs. "Well, don't count your chickens, is all I'm saying."
May grabs the two of them and starts hauling them down the road, away into another cold Irish night. "Bye," they all call out stumbling happily. I turn and walk the other way, back towards my hotel.
Palm trees are fun - but these guys are better.
Where is your favourite island? Do you prefer beaches and palm trees or culture and craic? Post your comments below.