A few weeks ago, I embarked on my first overseas trip to go to Copenhagen for this year's European DrupalCon. It was my 4th DrupalCon to date, but I've been wanting to attend one of the European ones for a while, as they have a reputation for having a different vibe than the North American ones (and of course so I could finally see some of Europe!)
The Core Dev Summit (+ Code Sprint Day)
Like the last conference in San Francisco, it was prefaced with the Core Developer Summit, which is a full day of presentations, discussions, and code sprinting on the core Drupal platform. The Core Dev Summit is the single day (twice a year at this point), where a good number of the people who work on Drupal core come together to take a step back and discuss in-depth any ideas or concerns. This often leads into some dedicated sprinting on core related issues (as well as some of the most crucial contributed modules).