prohibited turn
The phrase 'giro prohibido' in Spanish translates to 'prohibited turn' in English. Essentially, this phrase is often used in traffic contexts to indicate that a specific turn or direction is not allowed. For example, you might see a traffic sign with this phrase informing that turning to a certain road or lane is prohibited due to various reasons such as road works, one-way road among other reasons. Understanding such phrases can be essential especially if you are driving in a Spanish-speaking region.
The sign says that you are on a no-turn road.
This sentence is telling someone what a sign indicates - that they are currently traveling on a road where turns are not allowed.
Because of an illegal turn, I had a car accident.
This sentence explains a situation where the speaker had a car accident due to making an illegal maneuver such as turning where this action was prohibited.
Ignoring that it was a forbidden turn cost me a fine.
In this scenario, the speaker did not take heed that a certain type of turn was against the rules and has been penalized in the form of a fine as a result.