My overwhelming memory of it was being sick, lots, and crazy traffic. Somehow, despite visiting a lot of European cities in my late teens and early 20s, I never returned. I very rarely travel these days (for very good reason) and I haven't been on a city break in ten years or more.
When French magazine Parole de Mamans announced that they would be bringing top bloggers from around Europe to their E-Fluent Spot (no jokes, please) blogging conference I really wanted to go. To be honest it could have been two nights in a Travelodge on the M25 and I probably still would have applied as long as it was childfree.