This trail becomes more beautiful and less crowded as you run away from the Lake Elkhorn loop.

The best trail I have actually gone one its not to long or short it’s perfect

My husband and I walked this trail yesterday. We attempted to go to the southern parking area near Annapolis and start at the end. We do not recommend this for walkers. The southern parking lot is about a mile away from the southern trail head, and you have to walk along a busy road in a bike lane. We felt very uncomfortable with this. Perfect for bikers, again, not for walkers. We were able to find a parking lot near a midpoint of the trail in Severn. Starting here is recommended. There are two lots with immediate access to the trail and Porta potties as well. The trail itself is very pretty with a wide level asphalt surface. Wide enough for some walkers and bikers. We definitely saw predominantly bikers on our journey, only a handful of walkers and joggers. And one rollerblader!

They have replaced slot of the trail this past winter. There are still some bumpy sections . But can’t beat the tranquility of the wood and the bay for a good ride. You can’t go flat out but you can get a good relaxing ride in. Go early it’s gets crowded at times

This is a pleasant escape from the city, largely running along the creek and through woods, but occasionally popping out and paralleling residential neighborhoods. There are also hiking paths off the trail.
I love that it's a full loop (no backtracking!). It's well-maintained and quite flat, so it would be appropriate for all abilities. The southeasternmost extension (behind brewery and post office) is not as well maintained.
The northwest end of the trail (off Harford Road) is about a block from Lake Montebello, which has bike lanes running around the lake (and, as of May 2020, the roads around the lake are temporarily closed to cars). So Herring Run + Lake Montebello forms a pleasant, no-backtracking, extended loop. Also, as of May 2020, Harford Road is under major reconstruction, so finding the entrance to the trail from the Lake Montebello end is a little tricky (there's a temporary path carved out that's quite rugged and may create accessibility issues for those with limited mobility).

I have been enjoying the C&O Canal towpath since I was a boy -- but I went for a bike ride yesterday (May 10, 2020) at the Monocacy Aqueduct and the path is now paved (I assume it's considered crushed stone). Yep, it's now "new and improved" -- not. One problem is that the trail now has a lower shoulder than the paved road. If you happen to get too close to the edge or pull off, you've got a bit of a dropoff which could be problematic. Another problem is that some of my fellow bicyclers seem to love the new surface as they now go flying even faster than before. Hiking on the paved trail is certainly not as nice as the previous dirt path. The feeling of getting away from it all has diminished and the trail has lost some of its charm. It no longer appears to be a path in the woods from a bygone era, but simply another bike trail. Pedestrians beware.

Even on a COLD WINDY May day, there were lots of walkers, joggers, and some bikers. Steep on either end of the trail and I’m guessing 6-8’ wide so 2 bikers can safely but SLOWLY pass. Lots of smooth, elevated trail & bridges (lots of warning signs “Slippery When Wet”) Would be very nice in heat of summer since it’s shaded the entire route & alongside the stream. Trail is in the floodplain so would not be advisable when streams are up.

This section is complete. Paved and spacious. Not much elevation but good for a jog with a stroller from one end to the other and back. What’s not to love? Parking ok Crownsville is limited (two larking spots, 3 including a handicap spot) but the Rt3 lot near end of Millersville Rd has plenty of parking.

Got on part of this trail, while on western Maryland trail