Brussels is the worst--when it comes to traffic congestion. That's not my opinion, that's the ranking from Tom Tom, the GPS manufacturer. The last time Tom Tom checked, in June of 2011, Brussels topped the list of European cities with the worst traffic congestion. Though there are indications that's changing.
European Cyclists' Federation had to tell me when I visited their office in Brussels.
Listen to Julian's amusement when I start by telling him after my biking trip to his office, riding in Brussels wasn't so bad. I was surprised by the bike lanes stretching up from Brussels Gare Centraal, but as Julian explained, they are, as in many American cities, a patchwork affair. Chloe and Julian explain how the gridlock can--oddly--benefit a cyclist.
Brussels, after all.