Although the trail description does describe this as 4.5 mile asphalt trail, the comments provide some very misleading information that might be helped by some broader clarification in the main trail description.
When accessing this Dismal Swamp Canal Trail (NC), you come in contact with a network of recreational park resources that are adjacent to, but have nothing to do with, the Canal Trail to which this entry refers.
1. The Dismal Swamp Canal Trail (NC), is as described is a paved section of trail from a south-end trailhead parking area at the intersection of Route 17 and NC Highway 343 N going north to the NC Dismal Swamp Canal Welcome Center. (Note that the trail and Welcome Center are on the east side of the canal, between the canal and Route 17). The actual trail length is about 3.4 miles. I don't know how the 4.5 mile distance in description is calculated. The following description is taken from the Welcome Center website (https://dismalswampwelcomecenter.com/hiking/).
"Dismal Swamp Canal Trail
This three mile paved trail begins at the southern end of the Dismal Swamp Canal Welcome Center/Dismal Swamp State Park off US Hwy 17 and meanders through a wooded area between the historic waterway and the historic highway, ending at NC Hwy 343. A 5 foot wide extension provides access for the trail to the Village of South Mills. This trail is beautifully maintained by Camden County Parks & Recreation."
I checked with the visitor desk at this welcome center and with the State Park Welcome Center (see below) and they both assured me that this was the only paved section of trail along the NC part of the Dismal Canal.
Note that this section of trail is maintained by Camden County Parks & Recreation.
Also note that the Welcome Center is home to a 150’ face dock along the Dismal Canal that provides a rest stop to nearly 2,000 boaters yearly. See https://dismalswampwelcomecenter.com/boating/
2. There is a swing bridge across the Dismal Canal, accessed from the Camden County Welcome Center parking lot on the EAST side, that leads to the NC Dismal Swamp State Park on the WEST side of the Canal.
See both https://dismalswampwelcomecenter.com/state-park/ and https://www.ncparks.gov/dismal-swamp-state-park.
Note that the Welcome Center and the State Park are entirely separate organizationally, and although they cooperate, they are run entirely separately.
The State Park has a system of "trails", although from the perspective of Rail-to-Trail and TrailLink.com users I think the designation of "trails" is a bit generous. The State Park bikeable trails are, for most of the mileage, nothing more than old logging roads, which are quite rough (large gravel, largely ungroomed, sections with tree roots making the trail quite rough, some sections not much more than a grassy overgrown path).
See the map at https://dismalswampwelcomecenter.com/wp-content/uploads/2017/07/DISW_mappad15.pdf
Most of the State Park trails (roads) run straight as an arrow in a grid pattern through the swamp. The main rectangle of the grid, which makes up the largest part of the trail mileage is bounded by Kim Saunders Road, Forest Line Road, Corapeake Road and Martha Washington Trail. It's a somewhat uninspiring ride. Gravel Bikers or MTBers may be more inclined to like this ride, but for the typical Rail-to-Trail rider, this isn't an expected experience.
The confusion in this TrailLink entry on "Dismal Swamp Canal Trail (NC)" is that there are comments referring to stuff that has absolutely nothing to do with the Dismal Swamp Canal Trail (NC). One comment refers to starting your ride up in "Chessie" (address is 1200 Dismal Swamp Canal). This is way up in Virginia! The Virgina part of the trail is, from what I've read, entirely different than the NC section. Another comment refers to the State Park trails, which again, have nothing to do with the Canal Trail. The State Park trails largely run perpendicular to and away from the Canal. (Comment that refers to State Park trails... "The trails are very well maintained. Despite all the previous rain, I had an awesome 23 mile ride and thoroughly enjoyed the day. The park Staff are very knowledgeable and friendly.")
If you are expecting a Canal Towpath (trail following the old towpath right along the canal) type experience which is more typical of other preserved canal trails in the Mid-Atlantic and NE canals, you will be sorely disappointed.
The State Park trails are what they are, and serve a purpose, although different than what the typical Rail-to-Trail user expects. I'm simply suggesting that this trial description needs to be clarified to make clear to what it does, and does not, refer.