Paderne Castle (Castelo de Paderne) was originally built as a Moorish stronghold during the period of the Almohad dynasty. While Paderne Castle dates back to the eleventh and twelfth centuries, the site on which it was constructed has a history which may stretch as far back as Roman times.

In 1248, Paderne Castle was taken from the Moors by the forces of Dom Paio Peres Correia, a commander in the armies of Portuguese King Afonso III.

Now a picturesque reddish-brown ruin, Paderne Castle is one of the seven castles shown on the Portuguese flag.