Dynamo Open Air is a festival in the Netherlands that was held (almost) every year between 1986 and 2005. It was reborn in 2008 as Dynamo Outdoor and in 2015 as Dynamo Metal Fest.

Dynamo Open Air was originally held in 1986 to celebrate the fifth anniversary of the Dynamo rock club in Eindhoven. It began with 5,000 people in the Dynamo parking lot. From 1988 to 1992, it was held at a local ice rink with 22,000 capacity. In 1993, the festival was moved to the Eindhoven military airport (Vliegbasis Welschap). In 1994, it became a three-day festival. In 1995, Dynamo Open Air reported 118,000 attendees. To this day, it is still the largest multi-day open air festival ever held in the Netherlands. This caused too much pressure on the Dutch infrastructure, leading to some of the longest recorded traffic jams in the history of the Netherlands. The lines to drive in were so long that people infamously barbecued bratwursts on the highway. As a result, the municipality forced the festival to limit its capacity to 60,000 in 1996. In 1998, the festival site and the airport had to be moved in order to build 6,000 new houses. The festival site is now the Eindhoven residential area of Meerhoven. The festival returned to the ice rink in 1998, with a halved capacity of 30,000. In 1999, it was held at Mierlo, but it was located next to a garbage dump with a noticeable odor, and the parking situation was insufficient. So it moved again in 2000 to the Goffertpark in Nijmegen.