These rivers, once part of a major fur-trading route, merge into a delta here. The delta contains significant, brackish tidal marshes. The area also features a number of historical sites: from ancient Indian communities dating back to 3000 BC, to fur-trading sites from the beginning of the 1800s. Although the park has no facilities for visitors, it does provide opportunities for backcountry canoeing and camping. Visitors should be equipped with wilderness and white-water skills.