Complex sentence: It was intended to be a base for campaigns into Germania and until its destruction during the uprising of the Batavians in 70 AD it was occupied by 8,000 to 10,000 legionaries, and was the main base of the "Classis germanica".
Split into simpler sentences: It was intended to be a base for campaigns into Germania. Until its destruction during the uprising of the Batavians in 70 AD it was occupied by 8,000 to 10,000 legionaries, and was the main base of the "Classis germanica".