Such impediments could cause a nasty wreck on a bicycle as Conor had learned on his last long trip. In the early days after the collapse he’d taken a multi-day bike trip to help the friend of a friend, and on his way home he’d hit a rock with his front tire, taking a nasty fall. Horses would be unconcerned with such debris. They could step over an obstacle in the same way Conor
He didn't hit 'a rock' but a patch of loose gravel on the road. See ending of 'Grace Under Fire' by this author.
