For a Dub born-and-bred, taking three organised tours of the city is like entering a parallel universe where you view the city from the inside out - like a goldfish in a bowl - opening your mouth in wonder at the things you'd be ashamed to say you'd never noticed before.
Starting, naturally, slightly sceptical of the proceedings, I came away surprised, amused and even having learnt a few things along the way.
Starting with the Viking Splash tour, a familiar sight to bemused Dubliners as it trundles through rush-hour traffic, I then opted for a two-hour walking tour of the city, followed by the hop-on-hop-off open-top bus tour, operated by Dublin Bus.
Those on the tours came from Canada, Scotland, England, South Africa, France, Japan, Italy and the US. There were students and retired people and, on one tour, a Dublin couple and their young son, looking for a different sort of day out.
On the Viking Splash tour, "Ivan the Viking", aka Donnchadh O Duinn, drove around the city, providing a quirky potted history interspersed with some Irish verse. It's difficult enough to drive in Dublin at the best of times, but doing it in an amphibious military vehicle, decked out in Viking regalia with 30 curious tourists aboard deserves a medal.
Tourists aboard the Viking Splash vehicle are encouraged to roar "a victory cry" at passers-by. We tried our Viking roar on the "opposition", which included other tour buses and especially any member of the Dublin Bus fleet. It was easy to see who on the streets was Irish and who was a tourist - the tourists waved back, the Dubs glared.
As we walked and bused our way around the capital it became apparent that the "Celtic Builder" has temporarily obliterated many of our historical sights. The Ha'penny Bridge, under refurbishment, is covered in scaffolding. The Liffey is dotted with machinery carrying out work on other bridges.
Trinity College, on the Nassau Street side, is covered with more scaffolding. Up Kildare Street, the National Library is also being renovated, as is the National Museum, just yards away.
But never mind. The Viking visitors seemed most taken with the Clarence Hotel."Anyone know who owns the Clarence?" Ivan asked. "U2" was the unanimous response.
Ms Carol Hunt, a mature student of history and philosophy, took a group of 35 on the official Historical Walking Tour from Trinity College, around Temple Bar and up to Christ Church and the controversial Civic Offices built over the Viking settlement at Wood Quay. She gets a lot of Americans on the tour. "They've all read Leon Uris's Trinity," she says.
The Europeans usually speak excellent English and they lap up the history. Dubliners, she says, often stop to listen.
Our group, including several American students from Pittsburgh, some Canadians, South Africans and English, attentively listen to the two-hour lesson in social, political and cultural history. One or two even scribble notes as they walk. We start in Trinity College where an American woman examines the cobbles: "The kids couldn't rollerskate very well here," she remarks.
Meanwhile, a younger female visitor, also American, looks ominously skyward and says to her friend: "The sun that was up for a whole half a second is gone." Waving his video camera, he tells her not to worry: "I got it on tape."
Two others guys chatted about the history lesson. "You know all that stuff about Brian Boru? It's not real. It sounds like there's a lot of stuff put into it. You know, like, what's the word? Historical fiction."
In Dublin Castle the Americans are tickled to hear the cobbles were laid especially for president Clinton, replacing the more practical tarmac just a short while before his visit in 1995 - "Clinton's cobbles". In the upper yard, Carol points out that scenes from the film Michael Collins - another work of historical fiction - were shot here.
Crossing the road at the top of Lord Edward Street, one of the Americans spots the Civic Offices - or what many Dubliners refer to as the "bunkers".
"That's, like, a really neat building. It's, like, the coolest thing around. They've got some really neat architecture." Viking bones rolled over beneath us.
The Dublin city tour was for anyone accustomed to the daily commute in the city, like being beamed into a public transport fairytale. Without warning, the driver breaks into song: an unembarrassed, full-blast belt of "I'll tell me ma when I go home, the boys `won't leave the girls alone".
This is only the beginning of it - the full busload of Japanese, American, French and English tourists is treated to a repertoire that would leave Foster and Allen gasping for breath.
He drops a group off at the Guinness brewery "the most popular stop on the tour". Then we're treated to Happy Talk, followed smartly by Oh Lord, it's so hard to be humble. Having had enough history, songs and stories, I drove home on empty roads to the suburbs with the singing bus driver's melodies still ringing in my ears.
For information on the Historical Walking Tours of Dublin, contact 01-8780227. Viking Splash tours is at 01-553000 and the Dublin City tour operates from a number of points around the city - contact Dublin Bus at 01-8734222