"Basically half of [San Mateo] - except for the oldest and the youngest - are here," said Zac Steele, a community organizer with the South Philly Latino-advocacy group Juntos.
The way migration occurs, says Steele, is through connections and networks.
"If my brother immigrates to Philadelphia, and he says there's a job for [me], then I come and then my cousin comes."
It's impossible to say for certain who the first Poblano was to arrive in Philadelphia. One possibility is Alfredo Aguilar, back in 1975. Aguilar, now owner of the Mexican restaurant Las Cazuelas, on Girard Avenue at the edge of Northern Liberties, hails from Izúcar de Matamoros in Puebla state. Aguilar's family was part of an early wave of Mexican migrants who came to Philadelphia in the 1970s.
Aguilar is an unusual case. Before 1980, very few people immigrated to the United States from Puebla, says Douglas Massey, sociology professor at Princeton University and co-director of the Mexican Migration Project. Migrants from Mexico tended to come from the western part of the country and settle in California and Texas.
Then, in the 1980s, with the economic slowdown in Mexico, Poblanos started to become part of a latter wave of immigrants. "Puebla's economy contracted much worse than other parts" of the country, said Robert C. Smith, a Baruch College sociologist and author of the book Mexican New York: Transnational Lives of New Immigrants.
Puebla, a landlocked place, has "always been very, very conservative" and is "not a great economic innovator" among the Mexican states, Smith said.
With places like Los Angeles already saturated with Mexicans, Poblanos went to New York, where there was a demand for labor, he said. Then in the 1990s, housing prices in New York rose, so immigrants, including Poblanos, moved to more affordable places like Philadelphia and to cities in New Jersey, Smith said.
In Philly, one man in particular, Efren Tellez, is credited with the trend of bringing families from San Mateo to Philadelphia.
Accounts differ as to how Tellez got here. One restaurant owner says Tellez, disoriented and lost, knocked on the door of his business around 1995.
Tellez was trying to get to New York, but got dropped off by a smuggler in Philadelphia instead, said this owner, who did not want his name published. So, when Tellez saw a sign for a Mexican restaurant in Philadelphia, he knocked. The owner hired him, and Tellez stayed.
Mario Perez, 35, a cousin of Tellez's, recalled his cousin's story a bit differently. He said that Tellez first went to New York around 1995, but didn't like it, so he came to Philly because a friend knew a little about the city.
Tellez, who passed away about a decade ago from ill health, "persuaded 30 or 40 families to come here," said Perez. "He say, 'I can spare my home; I can find a job for you.' "
Tellez persuaded Perez to leave San Mateo, too. When he first arrived, Perez lived with Tellez, who helped him get his first job as a dishwasher at a restaurant near 19th and Chestnut.
"He do everything because I don't even know how to speak English," said Perez, who now has his green card. "He does the same for the other people [too]. He was very helpful."
Another factor in Poblano migration from New York to Philly was the Sept. 11, 2001, attacks, which deeply affected the service economy in New York, forcing many immigrants to look for work elsewhere.
The Sept. 11 attacks had "a very big effect because many of these guys worked in restaurants, and the restaurants got hammered," said Smith.