Tweedsmuir Park is approximately 480 kilometres by air northwest of Vancouver. The park is bounded on the north and southwest by the Coast Mountains and on the east by the Nechako Plateau. The park is south of Highway 16, approximately 90 to 100 kilometres, between Burns Lake and Houston.
The Nechako Reservoir (Ootsa and Whitesail Lakes) is the main access route to the northern region of the park but boaters must use caution when travelling on these lakes as the shoreline is a forest of drowned trees and floating debris that create hazardous boating conditions. A number of channels have been cut through the dead trees to give access to emergency landing areas. These provide shelter from the sudden and strong winds that funnel down the lakes from the Coast Mountains.
Two common access points to the northern portion of Tweedsmuir Park are Little Andrews Bay Marine Park and Wistaria Park. See those pages for travel directions.