(CNN)The Buenos Aires railcar on Line A is air conditioned and sparkling new, as is its destination, Flores metro station.
How to make a Pope: On the trail of Francis in Argentina
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I'm sure it's just a coincidence that Pope Francis comes from Flores.
It's because of the pontiff that I find myself at 3 p.m. outside the Basilica of San Jose, an 1880s church with a facade of Corinthian pilasters and an impressive Italianate clock tower.
It seems a gigantic church for a minor middle-class parish, but in the 19th century Flores was the abode of prosperous landowners whose estates hosted political conferences and witnessed lavish parties.
I'm here to join a walk to the Pope's old stomping grounds.
Daniel Vega, a guide with a booming voice and clearly enunciated Spanish meets me and three ladies from northern Argentina.
This being Latin America, we spent the first 15 minutes getting to know each other.
Our tour starts in the basilica because, as Daniel maintains, a 17-year-old Jorge Bergoglio -- now known to the world as Pope Francis -- had his epiphany in that confessional on our left.
"It was September 1953, springtime," says Vega. "Jorge was off to meet his friends who were waiting in the square. When he passed by the basilica, somehow he felt the need for a confession.
"He heard no voices, saw no visions, but that confession was a transcendental experience. He left with a strong conviction that he had to become a priest."
What about his friends?
"He forgot about them and went home."
Outside, Vega gives us the back story.
How the Bergoglio family had a candy store in Portacomaro, in Italy.
How they left for Argentina on the steamer Giulio Cesare in January 1929 to escape the fascist regime of Benito Mussolini.
Daniel adds that delays in selling their shop made them miss the earlier sailing of Principessa Mafalda.
It sank in October 1927 off the coast of Brazil with the loss of 314 lives.
Whether true or false, this act of apparent divine providence has already entered popular mythology.
The Pope's popularity has helped local businesses.
In front of us stands a pizzeria, cheekily named "Habemus Pizza y Pasta" after the traditional "Habemus Papam" announcement following a pope's election.
A team of Argentinian ice cream makers have already presented His Holiness with his own ice cream flavor: vanilla and lemon, in the papacy's traditional colors of white and yellow.
We stop in front of a white one-story terraced house at Calle Varela 268.
There are bars on the windows and the twin external doors lead to two separate flats.
It's all so ordinary except for the plaque: "Pope Francis was born here."
Until October 2014 another address at Calle Membrillar was considered to be the Pope's childhood home.
Indeed, when this tour started Pope Francis asked: "Which house do they go to?"
When asked what he meant, he waved it away: "Let the poor neighbors live in peace."
Not any more.
This address was discovered by historian Daniel Vargas who dug out the Pope's birth certificate and sent a copy to the Vatican.
Imagine his shock when his office phone rang: Pope Francis wanted a word.
It was a word of confirmation.
Little Jorge Bergoglio spent the first five years of his life here.
Only when the family expanded did they move to a bigger house at Calle Membrillar.
There's no doubt about our next stop a few blocks south.
A bright red exterior announces Escuela Pedro Antonio Cervino, a mixed primary school that Pope Francis attended.
The pervading silence is a reminder that it's summer vacation time.
After Cardinal Bergoglio's election as pope, an elderly neighborhood woman claimed to have been his childhood sweetheart.
"He wrote me a love letter", she insisted. "And said that if I didn't marry him, he'd become a priest!"
The media demanded to see the letter.
"When my father saw it, he tore it to pieces," she said.
"We were only 12!"
The media swooned.
Further south, the barrio becomes more residential.
A small breeze hits us as we climb uphill.
We walk by several freshly painted colonial-style houses with well-tended patios.
The Pope's father was an accountant and was comfortably off.
At Membrillar 531 we find the house where Jorge Bergoglio spent his youth.
As a marker of the Pope's past it scores high in disappointment, because it's been comprehensively rebuilt.
The Buenos Aires Tourist Board must have been greatly relieved when the more photogenic Varela residence was discovered.
Opposite there is a square where Pope Francis played soccer as a kid.
He's still a card-carrying fan of his local team San Lorenzo de Almagro (nickname: The Saints).
After his election San Lorenzo wore his image on their shirts for the next match.
They won 1-0 after their opponents scored an own goal.
No one here doubts it was a miracle.
The final stop blessed by the presence of Pope Francis is the kindergarten in the Misericordia College.
This is where he had his first communion and learned to count to 10, jumping down the entrance steps.
"He returned to the college afterward as archbishop of Buenos Aires", says Vega.
"They still remember how he helped wash the dishes".
It's probably because of memories like these that Pope Francis has his own tour.