We were staying at Camden State Park in Lynd at the lower campground and started the ride from there. The actual trail starts at the visitor center about a mile up a steep and winding road. However, there is a better route (CR-25) right from the campground through local streets in Lynd. Ask at the visitor center for more information.
The trail towards Marshall is mostly downhill. Initially the trail parallels highway 23 but this highway is one with low traffic (in my opinion). The trail eventually leaves the highway and goes through parks and open space park along River Road before entering the outskirts of Marshall. We went as far as the fairgrounds and turned around.
There are no mile markers along the trail. There is no sign to indicate that you are actually on the Camden Regional Trail. What signage there is is poor. Signs like “Trail Crossing” indicate the direction of the trail. Some signs simply read “Bike Trail.” There are some benches along the trail and a vault toilet at the trailhead at the parking lot on River Road but no other amenities (no water). The trail surface was in excellent condition. On the way back to the campground, we had a headwind plus a slight uphill grade. Just a reminder, this is not a rail-to-trail bike trail so you won’t have a flat ride but will have mild undulating terrain. I would recommend this trail if you are in the area but try to start in Marshall first so you go downhill on your return. :)