The festival opens with Lost Dream, staged by the Theatre of the Eighth Day from Poznań, western Poland.
Inspired by the legacy of Franz Kafka, the show evokes some of the characters and stories from his works, such as The Metamorphosis, The Trial and In the Penal Colony.
Held under the motto "Wanderings in Time," this year's festival explores memory, transience, ageing, migration, ecology and climate change.
The programme features street theatre, puppet performances, circus acts, workshops and family events, as well as evening jam sessions.
Founded in 1997, FETA has grown into one of Europe's largest open-air theatre festivals.
This year's event features artists from countries including Poland, France, Belgium, Germany, the Czech Republic, Spain, Estonia, Switzerland and Italy.
(mk/gs)