Hadn't heard of it. Sounds like they got the wrong Concord! I see it finishes on a good (pass or be passed) stretch from the water tower in. Have not been on the trails west of Fisk St. It does a stop-turn around at Loop Rd. which I've been on, avoiding the dip in Pleasant when running...
Take a
look at West End Farm Tr. between the Audubon Center and Carter Hill Orchard. It's about 7 mi. You could run 14 (!) or or get a ride from one end to the other and run back to the car. I'd be glad to give you a ride some spring day. Beth helped me out with it a few times.