Last section of bicycle trail connecting Pittsburgh, Washington, D.C., set to open – Post-Gazette
On my list of things I really want to someday is the approximately 335-mile bike ride from Pittsburgh to Washington, D.C. via the Great Allegheny Passage and the C&O Canal Tow Path. The Great Allegheny Passage is expected to be officially completed in June.
Mind the GAP & avoid getting in a rut
The trail has a packed crushed limestone surface for a smooth ride. Built mainly on abandoned rail beds, the trail is nearly level with the average grade of less than 1%. The steepest eastbound grade – 0.8% – is from Harnedsville to Markleton and Garrett to Deal. The steepest westbound grade is from Cumberland to Deal at 1.75%. Near the Big Savage Tunnel, the trail crosses the Eastern Continental Divide. From that point going east, the trail drops 1,754 feet in 24 miles to reach Cumberland and, going west, it drops 1,664 feet in 126 miles to reach Pittsburgh.
From Cumberland to Washington, DC, you drop 625 feet to sea level on the C&O Canal towpath. The towpath is overall much less improved than the GAP, as it was built for mules and not railroads. Be prepared for ruts, tree roots, mud and mosquitoes.
2012 story from The Post that I never got around to blogging: Biking the Great Allegheny Passage and C&O Canal from Pittsburgh to D.C.