A painting by the Austrian artist Gustav Klimt which was stolen in 1997 has been found again, hidden in a wall of the Italian gallery where it was taken from.

Workers discovered the painting, a portrait of a young woman done in 1917, when they cleared ivy from the outside wall of the Ricci Oddi gallery in Piacenza. They found a small trap door, which when opened revealed the painting inside a rubbish bag.

Police took charge and experts examined it to check its authenticity.

The painting completely vanished in February 1997. At the time Police believed thieves had used a fishing line to hook the painting off the wall and haul it up through a skylight to the gallery roof where the frame was found.

To deepen the mystery, a forgery of the painting, posted to a disgraced politician, was seized by authorities a three weeks later. However at the time of the theft the gallery had been searched thoroughly.

A spokesperson said considering the painting was close to the ground for 22 years it is in excellent condition.

The Klimt was second on the list of most valuable art missing in Italy, just behind a painting by Caravaggio stolen from a church in Sicily in 1969.

The Klimt is considered particularly important because shortly before its disappearance an art student realized it was painted over another work previously believed lost - a portrait of a young lady that had not been seen since 1912 - making it the only “double” Klimt known to the art world.

To see some of the other breath-taking art at the Ricci Oddi gallery visit: