For the Nuxalk people, salmon from South Tweedsmuir's waterways have had significant cultural and economic importance.

In 1793, British explorer Alexander Mackenzie travelled through the area of the park on his journey to the Pacific Ocean.

He became the first European man to see the Pacific coast of North America, 12 years before the more famous Lewis and Clark Expedition.

[3] In August 1937, Governor General of Canada John Buchan, 1st Baron Tweedsmuir travelled extensively by float aircraft and horseback in the area of the park.

He and his party were greatly impressed by the magnificence of its pristine wilderness, so much so that he encouraged the provincial government to preserve it.

[citation needed] Tweedsmuir Park is located east of the Kitimat Ranges in the western interior of British Columbia.

The park covers almost one million hectares and spans four regional districts: Bulkley-Nechako, Cariboo, Central Coast, and Mount Waddington.

[6] Tweedsmuir Park protects the entirety of the Rainbow Range, a collection of volcanic peaks where heavy mineralization has given the soil an array of colours.

The park also protects Hunlen Falls, a 260 metre tall waterfall with one of highest unbroken drops in Canada.

[7] The park was also home to Lonesome Lake, famed for homesteader and conservationist Ralph Edwards, who worked to preserve migration habitat there for the trumpeter swan.

This trail would later be used by British explorer Alexander Mackenzie to become the first European to transit the continent by land and see the Pacific Ocean.

However in the lower regions closer to the Bella Coola Valley the temperature is warmer with a higher annual level of rainfall.

Further west as the altitude climbs the weather is generally more severe and the temperature changes throughout the summer and winter are drastic.

[20] Drought conditions in the fall of 2022 significantly reduced that year's salmon population, affecting many other species depending on its survival.

[21] The park also frequently suffers mountain pine beetle infestations due to milder temperatures in winter.

[22] Tweedsmuir South Provincial Park hosts opportunities for angling, hiking, horseback riding, camping (both front-country and backcountry), and canoeing.