Some places it's not allowed but others it's fine. The more urban and suburban areas enforce the leash rules where as rural areas could care less.  This trail in particular was fine. All the dogs were off leash but I still stop to put my dog on a leash if I see another dog coming because  he doesn't realize that all dogs may not want to say hello. But even so, he's a very obedient dog (so much $$$ into training plus he's a very timid dog so if you raise your voice slightly he gets scared he'll get in trouble and comes).