The Palazzo dei Diamanti is hard to miss, with its entire exterior covered in more than 8,500 faceted marble blocks. This unusual (and famous) example of early Renaissance architecture was, like the palace of Ludovico il Moro, part of Duke Ercole I d'Este's Addizione Erculea (Herculean Addition), a plan to remake Ferrara in the late 1400s. Today, the palace contains the Pinacoteca Nazionale (National Gallery), with works by 13th- to 17th-century painters of the Ferrara school, and on the upper floor, changing exhibitions in the Gallerie d'Arte Moderna e Contemporanea feature major works by impressionists, post impressionists, and other later artists.
