Lots of early medieval stonework came to light when the Abbey was excavated in the 1960s. Now, in the bowels of the Abbey, you can delve into the site’s Early Medieval origins. In these vaults you’ll see building blocks from 8th to 17th century and remnants of the Carolingian and Gothic churches that preceded the existing cathedral.
The Cellar exhibition is well done and worth a visit. The touch screens with about seven languages, are are filled up with some information. There is a good film on the history of Gallus and his fellow Monks (unfortunately only in German, with German Subtitles).
One of the highlights of the exhibition is the Evangelium Longum. The magnificent binding of this book was created around 895 by the monk and artist Tuotilo. And there is a book which was made for Alexander the Great with ivory carvings.