It was established on March 29, 1972 to commemorate the location of the first railway in the province of British Columbia.

Covering only 0.7 hectares (1.7 acres), Seton Portage is the smallest provincial park in British Columbia.

Known as Dozier's Way after its proprietor, Carl Dozier, the roadbed of the route remains today as the route of most of Portage Road from Nkiat to the "downtown" of Seton Portage to Slosh, though part of its route is preserved by the historic park(Nkiat and Slosh are two First Nations villages which are where the one-time gold rush ports of Wapping and Flushing were located).

The Lillooet Cattle Trail was built through the same route as the Douglas Road but, despite an ingenious and fragile catwalk along the cliffs of eastern Seton Lake, was not usable in the long run and was abandoned and derelict by the time the Pacific Great Eastern connected the Seton communities to Lillooet in 1915.

[5] Passenger service to this location is no longer available, other than a local run from Lillooet, on the Canadian National Railway line.