Psy-Fi is an annual open air psychedelic music and arts festival in the Netherlands. The first edition was held in July 2013 in the Stadspark of the city of Groningen; all subsequent editions have been held in recreation area De Groene Ster to the east of Leeuwarden. It is one of the largest international festivals in the Netherlands and attracts thousands of visitors each year, with the 2017 edition reporting participants from about 100 countries. In 2019, project leader Wiebe Kootstra stated that only 18% of the attendees lived in the Netherlands, the rest visited the festival from abroad.