Castel Nuovo, better known locally as Maschio Angioino, looks the way a castle should look - fierce stone, towers and turrets. Built as the new royal residence between 1279 and 1282 by Charles I of Anjou, it is rightfully one of Naples' most striking buildings. Mind you, most of what we see today was built in the 15th century by the Aragon king Alfonso V, and via later renovations. At the end of the 15th century, Naples was annexed to Spain and the castle was downgraded to military fortress, but Charles III moved back in as King of Naples in 1734 restoring it to a royal castle.
These days Castel Nuovo, once scene of papal resignations, artists' parties including Giotto, Plutarch and Boccaccio, and fierce battles, is today home to a museum exhibiting 14th and 15th century frescoes and sculptures, silver and bronzes, and paintings by Neapolitan artists from the 17th-20th centuries.
Located near the port area of Naples, bus number R2 will take you to the New Castle. Get off at the stop for Piazza del Municipio.