In Portugal, there's an old saying whenever someone leaves but forgets to close the door behind them. "és de Braga?" or Are you from Braga? is the common reaction.
Braga is one of the oldest Portuguese cities: just about 90 minutes north of Porto, it was once an 'administrative' center during the Roman Empire, and an important road passed through it. It has the one of the oldest Portuguese cathedrals and the church of Bom Jesus de Braga is a pilgrim destinations set atop a massive amount of stairs.
But Braga breathes a younger spirit these days. Known for its cultural and arts scene, its colleges, the religious heritage and traditional festivities come across a modern lifestyle and the city has been drawing attention from international visitors.
But, "what does all of this have to do with doors?"
No, they're not big doors manufacturers and yes, they do close their doors. It gets cold up there in the winter.
Even though there's many theories around this saying, the most common explanation in the Arco da Porta Nova, or New Door Arch, that introduces visitors to the old part of the town. This Arch was built by the order of the archbishop Diogo de Sousa back in the 16th century. It was made during the city's growth as at the time there were no conflicts or battles going on, and the city expanded beyond its old walls.
So, a New Door was actually never built. Only the Archway. From there on, people from Braga started to be known as the ones who leave their door open.