The “Ion Ionescu-Quintus” Museum of Art, Prahova County, originated from the Ploiesti Pinacotheca, founded in November 1931. During the Second World War, the Ploiesti Pinacotheca was evacuated and was re-established in 1955 as the Ploiesti Art Museum. The building that houses the museum is a monument of national architectural value, included on the list of historical monuments. The palace was originally a private residence bearing in medallions the initials of its first owner - the politician and banker Ghiță Ionescu (1833-1898). He built and decorated his house between 1885 and 1894, according to the plans of the Romanian architect Leonida Negrescu, trained at the École des Beaux Arts in Paris and deeply influenced by the personality of Charles Garnier (1825-1898), creator of the Grand Opera in Paris (1861) and the most important representative of the Second Empire style.

The museum patrimony includes, mainly, modern and contemporary Romanian art (19th and 20th centuries) and is divided into collections: painting, graphics, sculpture and decorative art. Some of the artists whose works can be admired in this museum are Constantin Lecca, Gheorghe Tăttărescu, Theodor Aman, Nicolae Grigorescu, Ștefan Luchian, Theodor Pallady, Gheorghe Petrașcu, Nicolae Tonitza, Nicolae Dărăscu, Iosif Iser, Ion Țuculescu, Constantin Piliuță, Oscar Han, Constantin Baraschi and Ion Irimescu.