The Piekweek is a 10 days event in summer, organised to celebrate the 120th anniversary of KSV Sanctus Virgilius, the largest student association of Delft. The event consists of activities and parties that are attended by 2500 - 3500 students a day. The first 2 days take place at Kloster Grafenthal in Koch, Germany. The rest of the event is organised on a location in Delft that is designed and constructed by the organisation of the event.