Prantl was born in
Pöttsching in the
Austrian state
Burgenland. He studied from 1946 to 1952 with the painter
Albert Paris Gütersloh at the
Academy of Fine Arts Vienna in
Vienna. As the
stone sculptor he became he was an
autodidact. He was the founder of the
International Sculpture Symposium. He held his first international symposium (
Symposion Europaischer Bildhauer) with 8 participants in the old quarry
Römersteinbruch in
Sankt Margarethen im Burgenland. Prantl was invited to exhibit work in the Austrian Pavilion of the
Venice Biennale in 1986. Prantl died of a
stroke at his home on 8 October 2010, a month before his 87th birthday. ==Decorations and awards==