
The Tuesday Night Skate has been taking place every year since 1999. During the 2000 and 2001 seasons around five thousand skaters would take part each week. The number has dropped in recent years due to the event becoming less open to beginners and more dominated by race-skaters. The organisers are trying to reverse that trend with their "Back to the roots" skate nights - newcomers are now encouraged and more emphasis is placed on having fun rather than racing.
See the TNS homepage, as well as the photos, route schedule and statistics, and the chat forum.
By the way, there's a similar event in Munich called the Münchner Blade Night. It takes place Monday evenings.