C&O Path trail make up

Looking for some feedback on how rough (roots and rocks) the C&O trail is, and if there are sections which are rougher than others.

The short answer is yes. The C&O Towpath surface varies over its length. Unless you divert to the paved Western Maryland Rail Trail (WMRT) that parallels the C&O for ~25 miles, the Towpath is an unpaved trail of varying surface types. The good news is that over the years, much of the native earthen surface has been improved via resurfacing with a crushed aggregate. However, there remains a number of “3R” (rocks roots and ruts”) sections as well as some that don’t drain well and will be muddy with significant or recurring rain.

Approaching and especially exiting the Paw Paw Tunnel to Little Orleans has one or more of the 3R’s present. In fact, the section from the Paw Paw Tunnel to Little Orleans has not been resurfaced (as of last August) and is less enjoyable especially during or following rain. Also, the trail approaching and after Great Falls is a more gravelly surface with some rocks. In general none of the rocks are particularly sharp. Of all my trips on the C&O, a few have been on a road bike with 28mm tires. That would not be my recommendation, but I wouldn’t buy another bike just to make the trip. Wider tires or a thick chamois would be desirable however. :-)

Hopefully, other forum participants can offer their experience and opinions as well.

As Rivnuts mentions, it has changed quite a bit over the years and each year gets a little closer to the GAP in terms of surface quality. The important point though is that it isn't all like that. Where it is, you have a fine crushed limestone that rolls nearly as fast as pavement. It's a joy, but you do have to keep in mind that it is not asphalt. Edges will be soft and where it's soft thin tires will sink.

In other areas, you will encounter a rougher aggregate, pea rock, and dirt. Where it is dirt, you may encounter mud, or ruts. It's been two years since my last ride, but Cumberland south to Oldtown was particularly rough. Over they years I have also frequently encountered "temporary" surface, following a washout or other repair activity, and these sections are typically a coarser gravel.

If you are planning a full ride, probably the most important thing is to just be aware of the varying conditions and plan for the unexpected.

BUT ... this is not rough/technical, single-track level hazard. And it also not (generally) deep gravel, or chunky gravel.

What is your concern? General curiousity, difficulty of riding, bike prep, etc?

What is your concern?