The Derletalfest is the largest open-air spectacle in the Hardtberg district. It has been taking place since 1985 and is organized annually by the district administration office. Since 2018, it has also included the "Rock im Tal" music festival, which starts at 5 pm.

The Derletalfest offers a good opportunity to get information about the work of the associations and the diverse club life in Hardtberg at numerous stands.

Clubs and organizations wishing to participate can contact the Hardtberg district administration office:  bezvst.hardtbergbonnde