River Trail and Red Tail Trail Loop

This easy route begins at the Foss Farm Trailhead off Bedford Road in Carlisle and travels through both Great Meadows National Wildlife Refuge and adjacent Carlisle Conservation Lands. From the trailhead, head northeast on the Foss Farm Loop and pass the community gardens—remnants of the area’s agricultural past—before turning right onto the River Trail. At the next junction, stay right to remain on River Trail as Red Tail Trail branches left. The route follows the Concord River north through floodplain forest, cattail marshes, and wet meadows, with frequent views of the surrounding wetlands. The River Trail heads north alongside the river before looping back to meet Red Tail Trail. Turn left here to return to the trailhead on a slightly drier path through mixed woods and open wetland edges. This area is part of a major migratory flyway, and hikers may spot herons, wood ducks, and other wetland birds depending on the season. Signs of beaver activity are also common along the riverbanks. Portions of the trail may be flooded depending on recent rain, and boardwalks help span wetter sections. Most of this route is managed by the U.S. Fish and Wildlife Service, and is open year-round to hikers only. While the neighboring Carlisle Conservation Lands allow other uses, dogs, bikes, and horses are not permitted in the refuge. With its quiet setting, rich wildlife, and connection to local land history, this is a rewarding option for a short day hike near Boston.