No, I don't mean the bridges that join two shores. I mean the excellent Spanish tradition of building bridges that join two holidays.
In Spain, if a holiday takes place on a Tuesday, people will do whatever they can to skip work on Monday. If Thursday is a holiday, people will avoid work on Friday. So: Thursday's a holiday, but Friday is a bridge. A bridge between Thursday and Saturday, of course. And we call that "building (or making) bridges".
It's not as bad as it sounds. Number one bridge builders are students at all levels, then teachers, then civil servants, and then everyone else. If you're not a teacher, your only way of making a bridge is to keep a few days out of your holidays to make yourself a long weekend here and there.
The best brigde of the year takes place this week. December 6th is Constitution Day, the anniversary of our Constitution. December 8th is a Catholic holiday. December 5th, 7th, and 9th may become bridges. And since this one is so long, some people don't call it a bridge: it's an aqueduct!