I couldn't even pull a trailer over some of the spots on our local urban trail. That's not a complaint by the way. We're incredibly fortunate to have a nice recreational trail through town where I live, and I love the challenge of the steep and rough parts when I'm riding a bike; it just means I have to take a different route when I'm pushing or pulling something. In truth, I hope the city doesn't ever "develop" out these rough spots.
_________________________
The journey is more important than the destination.