There's a road on my regular ride that has a grate embedded in it at the wrong orientation so that a road bike's tires would get caught in it. I saw it for the first time about ten feet in front of me going 30 mph (it's at the bottom of a steep hill). That's when I learned you can actually jump in a bike. I've been regularly complaining about this thing to the township for the 15 years since, to naturally no effect.