When Londinium became a , the whole city was re-planned and a new great forum-basilica complex erected, larger than any in Britain. Londinium's basilica, more than long, was the largest north of the Alps and a similar length to the modern St Paul's Cathedral. Only the later basilica-forum complex at Treverorum was larger, while at Rome only the Basilica Ulpia exceeded London's in size. It probably had arcaded, rather than trabeate, aisles, and a double row of square offices on the northern side, serving as the administrative centre of the , and its size and splendour probably indicate an imperial decision to change the administrative capital of Britannia to Londinium from Camulodunum (Colchester), as all provincial capitals were designated coloniae. In 300 Londinium's basilica was destroyed as a result of the rebellion led by the Augustus of the break-away Britannic Empire, Carausius. Remains of the great basilica and its arches were discovered during the construction of Leadenhall Market in the 1880s.
When Londinium became a , the whole city was re-planned and a new great forum-basilica complex erected, larger than any in Britain. Londinium's basilica, more than long, was the largest north of the Alps and a similar length to the modern St Paul's Cathedral. Only the later basilica-forum complex at Treverorum was larger, while at Rome only the Basilica Ulpia exceeded London's in size. It probably had arcaded, rather than trabeate, aisles, and a double row of square offices on the northern side, serving as the administrative centre of the , and its size and splendour probably indicate an imperial decision to change the administrative capital of Britannia to Londinium from Camulodunum (Colchester), as all provincial capitals were designated coloniae. In 300 Londinium's basilica was destroyed as a result of the rebellion led by the Augustus of the break-away Britannic Empire, Carausius. Remains of the great basilica and its arches were discovered during the construction of Leadenhall Market in the 1880s.