Castle of el Castellet Monument · Piera, Anoia, Barcelona Image of Piera, not of the place itself. El Castellet stands on a hill 361 metres high, on the boundary of the municipalities of Piera, Vallbona d'Anoia and Cabrera d'Anoia, in the comarca of Anoia. At its summit survive the remains of the medieval fortification that gives the place its name. Photo: Friviere (CC BY 3.0) What to see and do in Piera