What is "pietrarubbia"

Pietrarubbia is a comune (municipality) in the Province of Pesaro e Urbino in the Italian region Marche, located about west of Ancona and about southwest of Pesaro.

It is home to an 11th-century castle which, according to tradition, is the ancestral home of the house of Montefeltro, rulers of the area in the Middle Ages and the Renaissance.