The first Roman Basilica in Londinium was built in AD70, with large scale expansion only 20 years later.
The new site was to be nearly four times larger (170m square) and took 30 years to complete, making it one of the largest construction projects north of the Alps.
A Roman basilica was a large public building where business or legal matters could be transacted. The first basilicas had no religious function at all.
The forum, consisted of three wings, enclosed a rectangular courtyard measuring 100m east-west and 85m north-south and contained shops, banks and offices with a central market place.