specially to Buda, helped this process. New thoughts were carried by the humanist prelates, among them Vitéz János, archbishop of Esztergom, one of the founders of Hungarian humanism. During the long reign of emperor Sigismund of Luxemburg the Royal Castle of Buda became probably the largest Gothic palace of the late Middle Ages. King Matthias Corvinus (r. 1458–1490) rebuilt the palace in early Renaissance style and further expanded it. After the marriage in 1476 of King Matthias to Beatrice of Naples, Buda became one of the most important artistic centers of the Renaissance north of the Alps. The most important humanists living in Matthias' court were Antonio Bonfini and the famous Hungarian poet Janus Pannonius. András Hess set up a printing press in Buda in 1472. Matthias Corvinus's library, the Bibliotheca Corviniana, was Europe's greatest collections of secular books: historical chronicles, philosophic and scientific works in the 15th century. His library was second only in size to the Vatican Library. (However, the Vatican Library mainly contained Bibles and religious materials.) In 1489, Bartolomeo della Fonte of Florence wrote that Lorenzo de' Medici founded his own Greek-Latin library encouraged by the example of the Hungarian king. Corvinus's library is part of UNESCO World Heritage. Matthias started at least two major building projects. The works in Buda and Visegrád began in about 1479. Two new wings and a hanging garden were built at the royal castle of Buda, and the palace at Visegrád was rebuilt in Renaissance style. Matthias appointed the Italian Chimenti Camicia and the Dalmatian Giovanni Dalmata to direct these projects. Matthias commissioned the leading Italian artists of his age to embellish his palaces: for instance, the sculptor Benedetto da Majano and the painters Filippino Lippi and Andrea Mantegna worked for him. A copy of Mantegna's portrait of Matthias survived. Matthias also hired the Italian military engineer Aristotele Fioravanti to direct the rebuilding of the forts along the southern frontier. He had new monasteries built in Late Gothic style for the Franciscans in Kolozsvár, Szeged and Hunyad, and for the Paulines in Fejéregyháza. In the spring of 1485, Leonardo da Vinci travelled to Hungary on behalf of Sforza to meet king Matthias Corvinus, and was commissioned by him to paint a Madonna. Matthias enjoyed the company of Humanists and had lively discussions on various topics with them. The fame of his magnanimity encouraged many scholarsmostly Italianto settle in Buda. Antonio