This afternoon I finished my traversal (on foot) of the short but interesting Four Mile Run Trail. The trail is one of two connections for cyclists looking to get from the Mount Vernon Trail along the Potomac to the Washington & Old Dominion Trail to Purcellville.
The path covers widely variable territory along its 7.5-mile length. The trailhead is in the neighborhood of the East Falls Church Metro station. In this stretch of Arlington, the trail serves to connect several county parks: ball fields and back yards. Although it’s very pleasant here, the trail can be hard to follow, because it intertwines with the W&OD as both trails cross and recross Four Mile Run, a rocky stream at this point—and the signage is inconsistent. Distance markers were once set every half mile, but a couple of them are missing. At points the trail is no wider nor any more level than a hiking trail, and this serves to divert bike traffic to the much busier W&OD.
At about mile 5, there is a complicated diversion onto city streets at Shirlington to take you to the overpass that spans an interchange of I-395 (the Shirley Highway), the multilane transitway that connects the heart of the city to all the suburbs to the south. Beyond that, the trail follows streets around the cozy brick community of Parkfairfax in Alexandria.
The last mile and a half of the trail follows the north shore of the channelized Run, which gradually widens out into an impressive floodplain. Before passing under U.S. Route 1 and Metro’s Blue/Yellow Lines and its connection to the Mount Vernon Trail at the airport, the trail passes a Dominion electrical substation and, perhaps most instructively, an Arlington County wastewater treatment plant. (Fortunately, the plant was nearly odorless on this hot summer day.) The Run, perhaps 50 m across now, entices a few shoreline fishermen, as it empties into the tidal Potomac River.