Peterborough ( ) is a city and county seat of Peterborough County, Ontario, Canada, about 125 kilometres (78 miles) northeast of Toronto. According to the 2021 Census, the population of the City of Peterborough was 83,651. The population of the Peterborough Census Metropolitan Area (CMA), which includes the surrounding Townships of Selwyn, Cavan Monaghan, Otonabee-South Monaghan, and Douro-Dummer, was 128,624 in 2021. In 2021, Peterborough ranked 32nd among the country's 41 census metropolitan areas according to Statistics Canada. The current mayor of Peterborough is Jeff Leal.

Peterborough is known as the gateway to the Kawarthas "cottage country", a large recreational region of the province. It is named in honour of Peter Robinson, an early Canadian politician who oversaw the first major immigration to the area. The city is the seat of Peterborough County, though it is politically independent from the county.

Peterborough's nickname in the distant past was "The Electric City" as it was the first town in Canada to use electric streetlights. This nickname also underscores the historical and present-day importance of technology and manufacturing as an economic base of the city, which has operations from large multi-national companies such as Siemens, Rolls-Royce Limited, General Electric, and local businesses such as Merit Precision Ltd., Dynacast, and Bryston. Electricity was one of the reasons Quaker Oats moved to the city, and as part of PepsiCo it remains a major fixture in the downtown area. However, over the years the number of major manufacturing plants has declined, and General Electric closed its last remaining facility in 2018. As a result, employment has been shifting toward the service industries and tourism is now the leading industry in the area.

History In 1615, Samuel de Champlain travelled through the area, coming down from Lake Chemong and portaging down a trail, which is approximated by present-day Chemong Road, to the Otonabee River and stayed for a brief time near the present-day site of Bridgenorth, just north of Peterborough.

19th century In 1818, Adam Scott settled on the west shore of the Otonabee River. The following year he began construction of a sawmill and gristmill, establishing the area as Scott's Plains. The mill was located at the foot of present-day King Street and was powered by water from Jackson Creek. This location, adjacent to the Ontario government Ministry of Natural Resources building, and Peterborough's Millennium Park may have been the site of landfall for a portage which connects in a direct line with Bridgenorth. The site has an Ojibway name "Nogojiwanong" which means "the place at the end of the rapids".

The year 1825 marked the arrival of Irish immigrants from the City of Cork to Scott's Plains. In 1822, the British Parliament had approved an experimental emigration plan to transport poor Irish Catholic families to Upper Canada.

Peter Robinson, a member of the Legislative Assembly of Upper Canada and a prominent businessman from York, Upper Canada was the man who took on the emigration plan of 1825. Scott's Plains was renamed Peterborough in his honour. Robinson interviewed families and individual males to make the long voyage. These families had to meet specific criteria in order to be eligible for the voyage. The specifics required for Robinson's settlers were that they had to be Catholic, poor and with a knowledge of farming. Males had to be less than forty-five years of age, in good health, and families were unrelated. The majority of the Irish emigrants were chosen from Fermoy, North Cork.Mannion, John. Irish settlements in Eastern Canada: a study of cultural transfer and adaptation. Toronto: University of Toronto Press, 1974. p. 219. Print

Robinson was urged by landlords to remove the "pauper and undesirables". He resisted and stated that he had "no wish" to hold out a bounty to persons of bad character. But as Robinson travelled through the countryside they became flesh and blood 'people of a good sort' he called them, 'bred to farming. I found them much more intelligent than I expected. Most of them could read and write'".Mackay, Donald, Flight from Famine: The Coming of the Irish to Canada (Toronto: McClelland & Stewart, 1992/ Reissued, Toronto: Dundurn, 2009), 59

Thomas Poole, a nineteenth century writer, wrote that all 2,024 passengers boarded nine ships in June 1825, with everything they owned, from Cork across the Atlantic Ocean to Quebec City. The journey took 30 days to cross the Atlantic, and on board the ship they were provided with bunks and food rations. Hard tack or ship biscuits were one of the many foods that were made to provide energy for the passengers. Hard tack was very easy to make and could be stored for months without spoiling. After the settlers landed in Quebec City, they travelled further down the St. Lawrence River, eventually reaching Lachine where they boarded a bateau, heading west to Kingston, and ultimately to Kingston and Cobourg. They camped in tents in Cobourg for several weeks until Peter Robinson joined them to lead them up to their final destination. The long voyage across the ocean was enough to weaken the emigrants but having to camp out in tents in the mid-summer heat brought on several other complications. Nearly all of the settlers experienced fever and ague, and several perished from it. Even faced with these hardships they forged ahead and put their trust in Peter Robinson, the man leading them to their settlement in Peterborough.Poole, Thomas W., A Sketch of the Early Settlements and Subsequent Progress of the Town of Peterborough: Peterborough, C. W., 1867, pp. 3–4.

In 1845, Sandford Fleming, inventor of Standard Time and designer of Canada's first postage stamp, moved to the city to live with Dr. John Hutchison and his family, staying until 1847. Dr. Hutchison was one of Peterborough's first resident doctors.

By 1846, the community was flourishing, with a population of about 2000. A stone jail and court house had been built and there were seven churches and various government offices. There was a fire company, two newspapers and a post office that received mail daily. Industry included two grist mills, two saw mills, one brewery, one ashery, two distilleries, three foundries, three tanneries and tradesmen of various types worked here. One school and one bank agency were operating.

Peterborough was incorporated as a town in 1850, with a population of 2,191.

Beginning in the late 1850s, a substantial canoe building industry grew up in and around Peterborough. The Peterborough Canoe Company was founded in 1893, with the factory being built on the site of the original Adam Scott mill. By 1930, 25 percent of all employees in the boatbuilding industry in Canada worked in the Peterborough area.

Peterborough would also see extensive industrial growth as one of the first places in the country to begin generating hydro-electrical power (even before the plants at Niagara Falls). Companies like Edison General Electric Company (later Canadian General Electric) and America Cereal Company (later to become Quaker Oats, and in 2001 PepsiCo, Inc.), opened to take advantage of this new cheap resource.

20th century

The first major events of the 20th century in Peterborough occurred in 1904. The first occurrence was the completion of the Peterborough Lift Lock on July 9, eight years after construction was initially approved. To this day, many landmarks in Peterborough memorialize Richard Rogers, conceptual father of the Lift Lock, such as Rogers Cove on Little Lake and Rogers Street in the eastern part of the city.

On July 1, 1905, Peterborough was incorporated as a city with a population of about 14,300. The city's flag and coat of arms were adopted later, in 1951.

In the 1970s, the Government of Ontario helped sponsor the building of Peterborough Square with the aid of the Ontario Downtown Renewal Programme (ODRP). The mall was anchored by an Eaton's store until the collapse of the Eaton's chain of stores in the late 1990s; it now houses offices, stores and a food court. The provincial government relocated the central office of the Ministry of Natural Resources to 300 Water Street, kitty-corner from Peterborough Square.

21st Century In 2008, the Peterborough Regional Health Centre opened, replacing the Civic Hospital and St. Joseph's Health Centre.

Lansdowne Place, the primary shopping centre in Peterborough, underwent a renovation in 2009, adding over 15 000 m2 (165 000 sqft) of retail space.

In September 2025, GE Vernova announced their plans to demolish the former General Electric factory complex, located at 107 Park St N. Despite controversy surrounding the plan for demolition, Peterborough city council approved GE Vernova's plan to demolish 26 vacant buildings on the property on October 14, 2025.

Geography Peterborough is situated in Central Ontario within the Kawartha Lakes region. Peterborough lies in the St. Lawrence Lowlands ecoregion, just south of the Canadian Shield and approximately north of Lake Ontario. The city is sited on a series of rapids in the Otonabee River, approximately halfway between the river's source (Katchewanooka Lake) and its mouth (Rice Lake). The city completely surrounds the only lake on the Otonabee, Little Lake, and the Trent Canal runs along the eastern edge of the city, connecting Little Lake to a section of the Otonabee above the rapids.

Topography

Peterborough's topography is largely defined by land formations created by the receding Wisconsian glaciers 10,000–15,000 years ago. The South End and Downtown portions of the city sit on what was the bottom of the glacial Lake Peterborough—part of a glacial spillway created when glacial meltwaters from ancient Lake Algonquin (now Lake Huron) travelled south to ancient Lake Iroquois (now Lake Ontario). This area of relatively low and flat relief (approximately above sea level) is prone to flooding, exemplified in the major flood that occurred on July 15, 2004. The ground elevation rises to the west, north, and east where a large upland area (the Peterborough Drumlin field) defines the landscape. Much of the land in the north and west ends of the city rises to above sea level, with Tower Hill, at above sea level, being the highest point. Armour Hill, another prominent drumlin located in east city, forms the physical obstacle that the Trent-Severn Waterway ascends by way of the Peterborough Lift Lock. The Oak Ridges Moraine is located approximately south of the city.

Climate

Peterborough has a humid continental climate (Köppen climate classification Dfb) with four distinct seasons. It lies in a transitional zone between areas to the south, which have a milder winter climate, and areas to the north (within the Canadian Shield), where the winters are snowier and sharply colder. Peterborough's Hardiness zone is 5b. Peterborough's climate can be quite unpredictable and vary greatly from one part of the city to another due to the effects of the Oak Ridges Moraine and changes in elevation. In the south end and areas south of the city, the Moraine acts as a barrier for weather patterns moving off Lake Ontario, reducing precipitation. In the north and west ends of Peterborough the effects of the Moraine are not as prominent, at times creating slightly cooler temperatures and more precipitation than the more southern parts of the city and county.

The highest temperature ever recorded in Peterborough was on July 11, 1936. The coldest temperature ever recorded was on December 21, 1871.

Significant weather events