Pennsylvania's Knox and Kane Rail Trail is 70-74 miles, depending on whether you ride or ignore the posted or obvious detours.
The endpoints are Marianne and Clarion Junction (near Clarion) and the Kinzua Bridge Skywalk near the town of Mt. Jewett. The Southwestern portion between Marianne and Marienville is asphalt-paved and can be ridden on almost any bike. The only obstacles will be crossings over gravel driveways or roads. Northeast of Marienville, the trail is still under development in places and the surface varies from fine crushed stone to overgrown single- or double-track. A few segments must currently be bypassed on adjacent roads. A gravel or mountain bike will be the best option in some areas. At minimum make sure your bike has wider, treaded tires (47-mm/1.8-inches or wider).
I rode the trail in July 2025 from Northeast to Southwest, taking advantage of the slight downhill trend in that direction. This also allowed me to get through the more challenging sections early in the trip. Here's a blow by blow of what to expect currently and in the future:
Kinzua Bridge Skyway to Lantz Corners: This 7.5-mile section begins with a couple of miles gently uphill (less than the maximum railroad grade, so probably 1.5% or so) and ends at Rt 219. The surface is a slightly larger crushed stone than elsewhere, but in good shape.
The official detour takes you onto Rt 219, then Rt 6 for 3.5-4.0 miles. You can access the trail again after you pass the Lebanon Lutheran Church (located on the south side of 6), via dirt or gravel drives at or just past W. Brick Rd (on the north side of 6). This gap is expected to be filled in the coming year, but if you are up for an adventure, it is possible to ride on undeveloped trail from 219 to Wolf Farm Rd (about 2.3 miles). The trail begins as double-track and degrades to unmowed single track (a slot through tall wildflowers). While you are doubting whether you are actually on a trail, you will unexpectedly encounter and cross a brand new wood trestle deck that was constructed in 2024 (490 feet long). At Wolf Rd, I diverted a few feet onto Rt. 6 due to swampy conditions on the undeveloped rail bed beyond. I hopped back onto the trail at the location noted above.
Once you are on fine crushed stone, you will continue for about 19 miles, passing through Kane, where services are available. There is short road detour in Kane bypassing an old trestle. Between Kane and Marienville, you are entirely within Allegeny National Forest with access to dirt and gravel roads.
At Sheffield Junction Rd, you'll turn right onto this coarse gravel road. While the Knox and Kane should continue across the road, that segment in eastern Forest County appears to be overgrown and not maintained. Some sections through the following miles may actually be rideable ("undeveloped" double-track as seen in Google's Satellite View), however on this day the trail crossings were heavily overgrown and bushwacking was not on my to-do list, as I was on a tight schedule. 2.8 miles of gravel on Sheffield, led to a short paved section of Watson Farm Rd/1005, and then coarse chip-n-seal pavement as Watson Farm heads south towards 66.
In theory you should be able to ride from Watson Farm Rd to 66 on double-track, and then cross the highway, finally looping back towards it further to the SW. I did not attempt this as the entrances off Watson Farm Rd, 66 and the NE bit of Byromtown Rd were all overgrown and/or invisible (unlike the Google Street View from the previous year). Recent posts (May 2025) seem to show rideable, if damp, trail near the loop crossing Byromtown and Ox Yoke Roads, about 0.7 miles south of 66. Unsure of the conditions, I just rode 66 SW to Byromtown Rd and Stayed on this street for 1.4 miles. A very unimproved section of the trail resumes here (watch out for the ditch not far in) and continues 0.7 miles to Forest Service Rd 226. At this dirt road a slightly-maintained (occasionally mowed) section of double track begins and continues to the outskirts or Marienville. There is a short 0.3-mile section of paved trail before Marienville, then more crushed stone until about 0.5 miles SW of town.
The paved surface begins just SW of Marienville and continues to the end in Marianne/Clarion Junction. You are in forest for much of the time until Leeper. The next section ending in Lucinda is often out in the open, with views of rolling farm fields. South of Lucinda the trail parallels Rt 66, hence the "Rail 66" moniker of the Knox and Kane Trail in this county. This last segment is also downhill enough for occasional coasting.
There is a brewery and DQ close to the south end of the trail. You deserve Beer and/or Ice Cream :)
Impressions:
Very quiet trail on hot, summer weekdays. I only encountered 2 riders going in my direction over the entire length of the trail, and saw maybe a dozen or so traveling in the opposite direction. Most folks were on e-bikes near towns. I always had the "undeveloped" areas featuring double track to myself. Enjoyed the ride!
Better information is needed on the websites, designating trail conditions or closures in the segments which have been rail-banked, but not developed or regularly maintained. Google Street View from 2024 often showed clear paths at intersections with roads, but the reality was quite different, with some areas so overgrown that the trail was completely obscured. Additionally, there was no signage at most of these intersections indicating the existence or status (open/closed/under developent) of the trail.
GPX file links for Navigation (my routes): When opening these RidewithGPS routes, choose the "OSM Cycle" map style to see the theoretical trail routes that I bypassed (labeled "KKRT," with track shown in purple). Day One - Kinzua to 66 at Watson Farm Rd. https://ridewithgps.com/routes/51975080 Day Two - 66 to Marienville (short 0.7-mile off-road section along Byromtown Rd not shown) https://ridewithgps.com/routes/51857805