As usual, I was really digging the performance of my Nokian Mount and Grounds for the three miles of ice/snow moguls I encountered through the woods. After that part of my commute I go through a couple of tunnels. This area is prone to water problems so I was prepared for shear ice. Well, as best I can ascertain, the water problem became an ice problem that the city decided to break up. Never the less, I had to hoof me and my 50 lb steed (heavy bike + load) through these ice boulders for about 300 ft. The bike path is to the left of the water and the last tunnel is at the far end of the photo. It's a crappy cell phone photo so you can't really appreciate that the entire length consisted of large chunks like those in the forefront sitting at different angles and orientation.

oof, that's rough. Not much choice there. A fat bike with studded tires would have gotten you over that nonsense (first hand experience here). That doesn't mean it would have been fun or easy or that you need to own one.