Through out Italy.
Normally a dried product made with durum wheat and water.
Acini di pepe pasta in Italian means “peppercorns”, they look like tiny beads. They work well in soups or cold salads. Also sometimes referred to as pastina (Italian for “tiny dough”); however, some pasta makers distinguish pastina as smaller than acini di pepe.
Ancini di Pepe
Source: Wikipedia List of Pasta