The Renaissance-revivalist architecture of Kalayaan Hall, now the oldest part of the Palace, combines the histories of the American, Commonwealth, and Second and Third Republics, on the grounds of the picadero pavilion of the Spanish period. It once glittered with Romblon marble embedded into the concrete of its façade, but subsequent coats of white paint since the 1960s have obscured this. Kalayaan Hall is today one of the most intact pre-war public buildings in the Philippines and has withstood the test of time, serving as link between the old and the new. The precast ornamentation, elaborate wrought iron porte-cochere and balconies, the loggias and high cellings ideal for the circulation of air under tropical conditions, all created a building of imposing appearance. For generations, the executive functions of the Philippine state were conducted in this building.
The main hall at the second floor of Kalayaan Hall was once the location of the guest bedrooms during the American era, and then of offices for the Office of the President during the Commonwealth. In 1968, it was cleared and renovated to form a large room called Maharlika Hall. It became the site for State Dinners and Citizens’ Assemblies during the Marcos administration. It was from the front west balcony of this hall that President Marcos took his last public oath of office and delivered his farewell speech on February 25, 1986. It was subsequently used as the Office of the Press Secretary until 2002, when it was transformed into the main gallery of the Presidential Museum and Library, with parts of the old State Dining table in the center, as well as the Gallery of Presidents, which is composed of objects and memorabilia – including clothing, personal effects, gifts, publications and documents – pertaining to the fifteen persons who have held the Presidency.