The low white building on the northwestern side of Plaza Grande is the seat of the Ecuadorian presidency. Visitors can enter by joining a free guided tour in Spanish and English which leave every 20 minutes; bring photo ID to the ticket office on Espejo to reserve a space. The President lives and works here, so sightseeing is limited to rooms that are not in use.
Inside the palace, the tour begins in the excellent new Museo de la Presidencia, with exhibits celebrating Ecuador's history, human rights and social justice themes and the country's biodiversity, and also displays of some of the 11,000 official gifts received by former President Rafael Correa. On the tour of the palace you'll see Andalusian patios (where bullfighting once took place), the cabinet room, banquet room, balcony and Presidents' room, where the portraits of Ecuador's constitutional presidents are displayed. At the staircase, don't miss Guayasamin's brilliantly hued mosaic depicting Francisco de Orellana's descent of the Amazon.