| Ashnola River | |
|---|---|
 Aerial view of the Ashnola River in 2017 | |
 | |
| Location | |
| Countries | United States and Canada |
| Basin features | |
| Tributaries | |
| • left | Similkameen River |
The Ashnola River is a tributary of the Similkameen River, rising in the northeastern part of the North Cascades in Washington, United States, and flowing north into British Columbia, Canada, to join the Similkameen River about halfway along that river's course between the towns of Princeton and Keremeos. The river crosses the international boundary at 49°00′00″N 120°19′37″W / 49.00000°N 120.32694°W and transits Cathedral Provincial Park. It has one main tributary, Ewart Creek, which is about 25 kilometres (16 mi) long and begins virtually at the border and is entirely within Cathedral Park.
A gravel road from its junction with BC Highway 3 at the locality of Ashnola flanking the river is the main, and virtually only, road access to the park. The locality of Ashnola was that of a mining camp from the days of the many gold rushes in the Similkameen Country and also the site of the Ashnola Indian Reserve (attached to the Lower Similkameen Indian Band).[1]