Lonely Planet review
The exquisitely balconied Palacio Arzobispal (Archbishop's Palace) to the left of the cathedral in Plaza de Armas is a relatively modern building, dating to 1924. On the northeast side, the Palacio de Gobierno was built in 1937 and is the residence of Peru's president. A handsomely uniformed presidential guard is on duty here all day; the ceremonial changing of the guard takes place at noon.
It's a struggle to get into the palace, which is by free guided tour only (Spanish and English) and has to be organized 48 hours in advance at the nearby Office of Public Relations. Ask a guard to point you in the right direction. On the corner of the plaza, opposite the cathedral, there is an impressive statue of Francisco Pizarro on horseback - though, just for the record, he was actually a mediocre horseman. The statue once sat in the center of the plaza, but the clergy apparently took a dim view of the horse's rear end facing the cathedral, so the statue was moved to its present position, with its backside safely averted. There is an identical statue in Pizarro's hometown of Trujillo, Spain.