The Muddy Branch Greenway Trail is a long natural surface trail that runs from the Potomac River to Malcolm King Park in Montgomery County, MD. The trail runs near the course of Muddy Branch, a tributary stream of the Potomac River that originates in Gaithersburg, Maryland.
The trail starts at Pennyfield Lock on the C&O Canal, then runs through Blockhouse Point Conservation Park, across River Road and on to Esworthy Road. From there, the trail crosses the road and enters Muddy Branch Stream Valley Park and continues in the park as far as Darnestown Road. At this point the trail leaves Montgomery County Parks. It then runs behind the Lakelands neighborhood in Gaithersburg, crosses private (but publicly accessible) property at the Izaak Walton League of America national headquarters, and ends on City Park land at Malcolm King Park.