High Park was opened to the public in 1876 and is based on a bequest of land from John George Howard to the City of Toronto.

Great blue herons can sometimes be seen there and at Lower Duck Pond, just north of The Queensway, where the water drains in pipes south to Lake Ontario.

In 2003, city workers found strong evidence of the pre-ice-age Laurentian River when capping two artesian wells at the pond at the north-east corner of the Park.

With this discovery, geologists finally pinpointed the southern terminus of this ancient river system whose southerly flow begins near Georgian Bay.

[6][7] The central section is a large plain encompassing most of the northern boundary, slowly narrowing to a point overlooking the lake, which is the location of Colborne Lodge.

While most of the plain is developed for picnicking, gardens and sports fields, it has a stretch of open habitat called oak savannah, of which there are few other examples in Ontario.

[4][8] Forested areas of High Park are maintained to mimic natural conditions, with downed trees left to decay.

Grenadier Pond is a large body of water 14.2 hectares (35 acres)[9] in size, located on the western edge of the park.

Largemouth bass, black crappie, yellow perch, pumpkinseed, bluegill, brown bullhead and carp sport fish are present in the pond.

The pond exits out to Lake Ontario via pipes near Sir Casimir Gzowski Park, replacing the natural sandbar that existed for Wendigo Creek.

[13] In 1836, John George Howard purchased a 160-acre (65 ha) property in the County of York, to the west of Toronto, for a sheep farm, at the cost of $1,000.

[14] It was here that Howard designed and built Colborne Lodge, a Regency-style cottage in 1837 to complement its natural surroundings[15][16] as the residence for himself and his wife Jemima Frances Meikle.

The name 'High Park' is attributed to Jemima, as Colborne Lodge is situated on the highest point of the Humber Bay shoreline.

[15] The Howards are buried in High Park, under a stone monument that is fronted by a portion of ornate fencing from St. Paul's Cathedral in London, England, across the street from Colborne Lodge.

[25] The public school was for children of "low vitality" and emphasized physical activity over academics and often held classes outdoors.

[28] The human remains were dated to between 2,500 BC to 800 AD, indicating some sort of indigenous peoples' presence at High Park.

In 1985, a group of five young teenage boys from Toronto suburbs went to High Park and beat to death a 40-year-old male librarian.

The site, a small hill known as "Snake Mound" on the west bank of Lower Duck Pond, had been eroded by illegal BMX bike use.

The society, in cooperation with the City of Toronto, cordoned off the location and worked to restore the site, fixing the erosion, and removing the bike ramps present.

The park also has sports fields, a hockey rink, a pool, tennis courts, playgrounds, nature trails and picnic areas.

From spring to fall, a "trackless train"—a tractor that tows several wagons decorated to look like a red and white train—is operated, making a tour of the park every 30 minutes.

Colborne Lodge is a historical museum located in an 1836 home built by John George Howard, an architect, engineer, and prominent Toronto citizen who was the first land-owner of High Park.

It offers programs for schools in the fall and spring, and day camps during the summer for children to learn about growing plants and Toronto parks.

[49] The High Park Nature Centre was awarded an Ontario Trillium Foundation grant in 2014, allowing for the purchase of furnishings to equip the much larger Forest School space and also to expand programming.

Recently, an Outdoor Urban Restoration Space (OURSpace) was developed with the assistance of a Weston Parks Challenge Grant.

High Park Zoo is a small collection of animals along Deer Pen Road, which rises from the eastern ravine up to the plateau near the Grenadier Restaurant.

The zoo keeps American bison, Barbary sheep, capybaras, emus, Highland cattle, llamas, mouflon, peacocks, reindeer, wallabies and yaks in eleven paddocks.

[77] High Park was used for cycling events for the 2017 Invictus Games, replacing Toronto Islands which was still recovering from flooding during the spring and summer.

The Volunteer Stewardship Program (VSP) is a volunteer group working with City of Toronto Urban Forestry and Horticulture staff, to protect and restore the remaining natural areas of High Park including large areas of Savannah with Black Oak trees and related flora and fauna.

Spring, summer and fall activities include planting, collecting seeds, and removing invasive species from restoration sites.