The beautiful architecture of the palace is exemplary of the European neoclassical style. The palace also boasts a decorative and exuberant interior, replete with an internal garden and water mirror, lined by royal palms.

The library itself, also known as the Biblioteca Embaixador Antonio Francisco Azeredo da Silveira (Ambassador Antonio Francisco Azeredo da Silveira Library), after the diplomat and former foreign minister, was built between 1927 and 1930, using sophisticated technology to reflect a time of modernization and administrative rationality.