Hills. Some cyclists love them. Some cyclists hate them. Personally, I would rather avoid them if at all possible. Cycling rail trails differs from road cycling. It is rare for a road cyclist to encounter a constant gradual climb that can last for many miles.
For rail trails in hilly to mountainous regions, the elevation gain is limited to 1% – 2% to allow trains to make the climb laden with their payload. The Cumberland to Deal section of the GAP is a very prominent example of a 20+ mile ascent gaining 1,800 feet in the process. Climbing is a struggle while descending is a piece of cake. See the GAP website illustration.
I analyzed the Cumberland to Big Savage Mountain section of the GAP during my 2011 tour planning. I chose to cycle west to east and enjoy the 22 mile coast into Cumberland in 2011. I chose to make the climb up the mountain on my 2014 tour. I definitely prefer the east to west option on the GAP.
East to West
The C&O Canal Towpath is relatively flat over its 186 mile course along the Potomac River. What gain it has is minimal. The 22 mile climb from Cumberland allows cyclists to put your power to the pedal and get the elevation gain out of the way in a matter of hours. Once the cyclist crests the Eastern Continental Divide, it is smooth sailing downhill into Pittsburgh. There are small dips and gains along the last 130 miles, but they are minimal. I love this long downhill cycle.
West to East
The first fifty miles out of Pittsburgh on the GAP is relatively flat with minimal elevation change. The next 75 miles to the Eastern Continental Divide climbs about 1,000 feet before cyclists enjoy the free downhill ride into Cumberland. As with any uphill climb, even one as minimal as 1-2%, cyclists spend most of their time pedaling and working against gravity. The C&O Canal Trail is easiest in this direction with a very gradual descent into Washington D.C.
It’s your choice
There are many opinions about the directional logistics. Many people are lined up in both camps. My first tour was self-supported. The west to east climb through Pennsylvania was difficult at times laden with 60 pounds of supplies and gear on my bike. I believe a self-supported tour would be easiest east to west.
There are many other factors that can influence your direction other than your love or hate relationship with hills and elevation change. I wanted to present my perspective on cycling the GAP and C&O in terms of elevation. Although I favor the east to west trek, I have no qualms with taking a west to east course on an upcoming ride.