In the old Synod Hall just across the road from the cathedral (linked to it by a bridge) you will find Dublinia, a rather touristy sight-and-sound re-creation (in five languages) of Dublin in medieval times; tableaux of medieval craftsmen and characters cover events in the city from the Anglo-Norman invasion (1170) to the dissolution of the monasteries (1540).
Dublinia is a recreation of Dublin from medieval times.