For the Romans, religion was part of the daily life. Each home had a household shrine at which prayers and libations to the family's domestic deities were offered. Neighborhood shrines and sacred places such as springs and groves dotted the city. The Roman calendar was structured around religious observances; in the Imperial Era, as many as 135 days of the year were devoted to religious festivals and games ("ludi)". Women, slaves, and children all participated in a range of religious activities. Some public rituals could be conducted only by women, and women formed what is perhaps Rome's most famous priesthood, the state-supported Vestal Virgins, who tended Rome's sacred hearth for centuries, until disbanded under Christian persecution and domination.