Final answer:
During ancient Rome, the nighttime was divided into four watches called vigiliae. The vigiliae system was used to protect and organize the city during the night.
Step-by-step explanation:
During ancient Rome, the nighttime was divided into four watches called vigiliae. Each watch was roughly three hours long, and the watches changed throughout the year based on the length of daylight.
The vigiliae system helped ensure that the city was protected and organized even during the night.
Learn more about vigiliae