Oregon City hulls made the conversion possible

The Albany class could carry such an extreme missile-cruiser superstructure because the ships began as heavy cruisers built to substantial wartime standards. The Oregon City-class baseline was 13,260 long tons standard displacement, 120,000 horsepower, 32.4 knots, radar, and nine eight-inch guns. Its original superstructure was comparatively modest, which makes the enormous topside volume added by conversion especially stark. This watch point establishes the hull, machinery, and armament that the missile rebuild had to transform.