Piedrasblancas is the capital town of the municipality of Castrillón, in the province of Asturias, Spain.

Piedrasblancas is a singular entity of population and has the title of Villa.

Piedrasblancas, located in the parish of Laspra, is within easy access by motorway to the main urban areas of Asturias (i.e. Oviedo, Gijón, Avilés), and many of its residents commute daily to those areas.

Although not properly in the coastline, it is within walking distance from the beaches of Salinas, Arnao and Santa Maria del Mar.

The climate is oceanic, characterized by mild winters and summers, with temperatures seldom exceeding 25 °C (77 °F) or going below 0 °C (32 °F).