Fodor's Expert Review Palazzetto Zuccari

This amusing palazzo was designed in 1591 by noted painter Federico Zuccari (1540–1609), who frescoed the first floor of his custom-built home. Typical of the outré Mannerist style of the period, the two windows and the main door are designed to look like monsters with mouths gaping wide. Zuccari—whose frescoes adorn many Roman churches, including Trinità dei Monti just up the block—sank all his money into his new home, dying in debt before his curious memorial, as it turned out to be, was completed.

Today, it is home to the German state-run Bibliotheca Hertziana, a prestigious fine-arts library. Access is reserved for scholars, but the pristine facade can be admired for free. Leading up to the quaint Piazza della Trinità del Monti, the nearby Via Gregoriana is quite charming and has long been one of Rome's most elegant addresses, home to such residents as 19th-century French painter Ingres; Valentino also had his first couture salon here.