The Meduxnekeag River is a tributary of the Saint John River, approximately 56 km (35 miles) in total length, originating in Maine and flowing north across the US-Canada border into New Brunswick, where it joins the Saint John at downtown Woodstock. In New Brunswick, the North and South branches cross the border separately and converge just below Jackson Falls on the South Branch, then flow approximately 25 km to the mouth at Woodstock. The final 2 km before Woodstock passes through an extensive wetland before the river widens into a basin and meets the Saint John.

The river is considered a moderately good paddling river. Like other rivers of its size, it can become quite shallow during dry summer months, which may limit paddling. Significant sections are suitable for canoe or kayak in high or medium water conditions, generally in May and June and again in September and October, with July and August also viable in wet summers. Annual canoe races are held in New Brunswick in May.

The traditional recreational route in New Brunswick begins below McBride Bridge on the North Branch, just above the confluence of the two branches, and takes out in downtown Woodstock — a half-day trip depending on pace. This stretch passes through mostly forested, scenic country. Walking trails within the Meduxnekeag Valley Nature Preserve are accessible from the river below Red Bridge. The Meduxnekeag Valley Nature Preserve is also noted for containing some of the richest remnant Appalachian Hardwood Forest in Atlantic Canada, with numerous rare understorey plant species.

Wildlife and natural interest along the river includes the edible fiddlehead (ostrich fern), harvested from the intervales and islands in May. The Meduxnekeag is one of only two New Brunswick rivers with a resident population of brown trout, and parts of the river are designated fly fishing only or hook-and-release. Smallmouth bass fishing near the river's mouth is also well regarded.

Canoe, kayak, stand-up paddleboard, and pedal boat rentals are available in Woodstock through Wolastoq Rentals, located on the Meduxnekeag and Wolastoq rivers at 577 Main St., operating from May through October.