 The city soon became one of the busiest trading ports on the Ligurian coast; but it had an important rival in the Roman town of Cemenelum, which continued to exist as a separate city until the time of the Lombard invasions.The ruins of Cemenelum are in Cimiez, now a district of Nice.In the 7th century, Nice joined the Genoese League formed by the towns of Liguria.