[5] Later, during the Dutch period, King William I of the Netherlands sponsored an expansion of the collection (1817 and 1819) and had two wings built on the current Place du Musée/Museumplein (the so-called Palace of National Industry, opened in 1830).

The works of the Old Masters (French: vieux maîtres, Dutch: oude meesters) were finally moved from the Palace of Charles of Lorraine to the Rue de la Régence/Regentschapsstraat in 1887, giving a new purpose to Alphonse Balat's Palace of Fine Arts (see below), which had opened in 1880 (not to be confused with the current Centre for Fine Arts).

The 15th-century rooms are devoted to so-called Flemish primitives such as Robert Campin (the Master of Flémalle), Rogier van der Weyden, Petrus Christus, Dirk Bouts, Hans Memling, and Hieronymus Bosch.

The Italian and French schools are also represented, notably by Carlo Crivelli, and the Master of the Annunciation of Aix-en-Provence (possibly Barthélemy d'Eyck).

[1] For English-speakers, the Landscape with the Fall of Icarus, by or after Bruegel, is one of the most famous works,[10] if only because of W. H. Auden's poem Musée des Beaux Arts.

Other paintings by Bruegel the Elder are: The Fall of the Rebel Angels,[11] Winter Landscape with a Bird Trap[12] and The Census at Bethlehem,[13] a group only matched in Vienna, as well as many early copies.

[17] The main building that now houses the Oldmasters Museum was built as the Palace of Fine Arts (French: Palais des Beaux-Arts, Dutch: Paleis voor Schone Kunsten).

[5][6] Built in an eclectic style of classical inspiration, it stands as an example of the Beaux-Arts use of themed statuary to assert the building's identity and meaning.

[19] On the side of the building, a memorial commemorates five members of the National Royalist Movement, a resistance group killed during the liberation of Brussels on 3–4 September 1944.

[21] Alongside the building's western face is a sculpture garden, landscaped in 1992, with works by Aristide Maillol, Emilio Greco, Bernhard Heiliger and Dolf Ledel [fr].

[18][22] Accessible via the Rue de la Régence, the vast rectangular main hall—formerly called the Sculpture Hall and currently the Forum—was designed as an interior courtyard overlooked by a colonnaded walkway and topped by a skylight.

It also gives access to a café with a terrace, open in fine weather, overlooking the sculpture garden and offering a panoramic view.

[23] At the far end, in line with the central hall, is the Balat Staircase, consisting of four straight flights, covered by a vault supported by two groups of Ionic columns, and lit by a high arched window.