I had heard about an airplane factory at Calle San Jacinto and there is actually a small sign on the wall (just by the bar "El Tejar") commemorating it. A bit googling around and I found this neat blog post telling the story. By the way, the hangars are still there, for example two of them are used as gyms.
In short, in the beginning of the 1900's, a car factory was operating in the premises and they also constructed some airplane engines. The old picture above shows the logo of the original factory, "Fábrica Hispano-Suiza de Automóviles". That portal is still on Calle San Jasinto. The truck is transporting an airplane wing to a nearly airport called "La Tablada", situated a bit further down the river, where Matt still goes running.
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Check the old advertisement with the drawing of La Giralda! A few links below about the planes and their history linked with Seville:
- El mundo (some mistakes with dates and names)
- El Saeta pictures
- some background about the Triana plane project
- More history