In 1810 a priest rang his church bells and shouted for the end of Spanish rule. Two centuries on, every town in Mexico still shouts back.

On the night of September 16 the plaza in Puerto Vallarta fills by seven, becoming a sea of flags, children in charro suits, grandmothers with trays of pozole. A bell sounds, the names of the heroes are called out one by one, and the crowd answers each with a roar.

No matter if you’re Mexican or not, it’s impossible not to join in.

They arrive without warning — a band, then five-metre people swinging their arms down the street, and nobody in Oaxaca looking up.

These gentle giants are built by hand from reed and paste, a month's work for a figure that will spend its life being bounced through a procession and nearly knocking somebody over. Somebody bends the carrizo. Somebody paints the face. Somebody teaches a child to do both. On the difference between a tradition kept behind glass and one still light enough for a new generation to climb inside.

For a century the enormous hall in Colonia Doctores built and repaired the streetcars that moved the capital, until Luis Buñuel turned up in 1953 to make a film about one, until the trams disappeared and the rooms filled with government paperwork instead.

Charlotte Smith explores the history of a building that found new work without pretending to be something it wasn't.