Peru is a country in South America.
Circa 1000 BC, the Exxilon visited Earth and helped build temples in Peru. The Doctor saw Exxilon markings on the walls of one temple. (DW: Death to the Daleks)
In 1910, the Doctor witnessed earth tremors in Peru. (MA: The English Way of Death)
In the 1970s, Sarah Jane Smith wrote an article criticizing tourists who didn't respect native customs in Peru. (ST: To Kill a Nandi Bear)
In 2009, Alistair Gordon Lethbridge-Stewart was stranded in Peru and thus unable to assist UNIT in the Sontaran invasion of Earth. (DW: The Poison Sky) He later returned to Britain for a while (SJA: Enemy of the Bane) but later returned to Peru and was unable to attend Sarah Jane Smith's wedding to Peter Dalton. (SJA: The Wedding of Sarah Jane Smith) He was still in Peru at the time of the Eleventh Doctor's supposed funeral and so was unable to attend. (SJA: Death of the Doctor)
When the Eleventh Doctor, Amy Pond and Rory Williams put on ponchos for warmth, Amy said that they looked like a Peruvian folk band. (DW: Amy's Choice)