A working day between a holiday and a rest day, taken off to join the two.
When a holiday falls on a Tuesday or a Thursday, the working day between it and the weekend is a bridge — a puente in Spanish, a pont in French, a Brückentag in German. Taking it turns a one-day holiday into a four-day one.
In most countries this is custom rather than law, and it is invisible to any calendar built from statutes: nothing closes, no instrument names the day, and a great many people are absent. In a few places it has been formalised, either by moving the holiday outright or by declaring the bridge in advance.
For anyone planning across borders the bridge is often more disruptive than the holiday it hangs from, because the holiday is in every calendar and the bridge is in none.
Substitution moves the holiday itself, by rule. A bridge day adds a day beside a holiday that has not moved.
The long weekend is the result. The bridge day is the working day given up to produce it.
See also long weekend · substitution · public holiday · observed but open
We hold this as not held as a distinct field — bridges are custom and mostly unpublished. See what we hold.