I saw the sign on my way to Omišalj and decided to take a look.
When you step off the road the path becomes rocky (it's more of a hiking path although there is a bike sign as well) and after 100-200m impossible to ride on. I have a gravel bike but since the rocks are fairly big I found it easier to push my bike than ride. The path is only 500m long so it's not that bad.
Around the fifth century, an early Christian basilica was built to the west of the Roman forum - although it was rather an impressive early Christian complex. Visitors can also marvel at the remains of this building today. Excavations are still being carried out in the area. A Benedictine abbey was later built on the site of the basilica, mentioned in documents of the then Pope from 1252. Stone blocks from the previously destroyed Roman forum of the city of Fulfinum were partly used for the reconstruction of this building.