The tomb of Emperor Frederick III (1415-1493) in St. Stephen's Cathedral in Vienna has been found to contain, among other things, a crown, a sceptre and an imperial orb.

Scientists explored the interior of the last untouched imperial grave in Europe with small cameras. The experts involved described the discovery as a "sensation" at the presentation of the results in Vienna this week.

In 2013, the scientists decided to risk a glimpse into the magnificent tomb, but the images and samples had to be analysed with great effort. To this end, the researchers used a small hole drilled into the tomb in 1969. At that time, the rumours that the grave was empty were refuted.

500 years after the emperor's final burial (1513), the scientists used this hole as an entrance for lighting and tiny cameras.

In addition to the insignia, the researchers found custom minted coins, a large crucifix with a statuette of Jesus and various textiles in the tomb.

The crown, probably mostly made of gold-plated silver, turned out to be the earliest surviving specimen of the type "Mitrenkrone", which was to become characteristic of the House of Habsburg in the following centuries.

With a reign of 53 years, Frederick III was the longest ruling head of the Holy Roman Empire. He was also the only Habsburg to be crowned Emperor in 1452 by the Pope in Rome in medieval tradition.

The tomb of the emperor in St Stephen's Cathedral in Vienna is considered a major work of late Gothic architecture. According to the researchers, a complete opening of the tomb was not possible without some degree of damage.