Location and Length
When completed, the 150-mile Great Allegheny Passage will connect with the 184.5-mile C&O Canal Towpath at Cumberland, Maryland to create a 334.5-mile traffic and motorized vehicle-free route between Pittsburgh and Washington, DC. The Montour Branch will, when completed, connect McKeesport to the Pittsburgh International Airport and Coraopolis.
Trail Grade and Surface
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 mosquitos.