Which festival is associated with the beginning of the grape harvest?

The festival associated with the beginning of the grape harvest is Vinalia Rustica. This celebration, which took place in ancient Rome on August 19, honored Venus as the goddess of vineyards and wine. It marked the time when grapes were ready to be harvested, and various rituals were performed to ensure a good crop and favorable conditions for the wine-making process.

During Vinalia Rustica, farmers and vintners would prepare their vines, offering sacrifices and performing rites to invite blessings upon the grape harvest. The festivities included drinking new wine and celebrating the fruits of the land, thus solidifying the festival's connection to viticulture.

In contrast, Terminalia was a festival dedicated to the boundary stones, Saturnalia was a midwinter festival honoring the god Saturn, and Parilia was a pastoral festival celebrating the shepherds and purification of cattle. Each of these festivals served different purposes and did not specifically relate to the grape harvest in the same way Vinalia Rustica did.