San Diego Civic Theatre in downtown San Diego debuted its 2,967-seat auditorium on Third Avenue in 1965, designed by architect Lloyd Ruocco as the region's largest indoor performing-arts venue. The theater serves as the permanent performance home for San Diego Opera, Broadway San Diego, and California Ballet, a trio of resident companies whose combined seasons fill the hall from September through June alongside event spillover from San Diego Convention Center's convention schedule. Ruocco's proscenium stretches 56 feet wide and nearly 30 feet high above a stage measuring over 134 feet across and 60 feet deep, with an 81-foot grid supporting 64 counterweight linesets for full-fly scenic capability. A September 2025 lobby renovation marked the theater's 60th anniversary, refreshing midcentury public spaces while preserving the four-level auditorium—orchestra, dress circle, mezzanine, and balcony—a sightline geometry that scales up from the intimate single-floor format at The Geoffrey Off Broadway in the Gaslamp Quarter. The most technically complex productions deploy the full 64-lineset fly system, orchestra-pit hydraulics, and multi-zone sound reinforcement across all 2,967 seats for large-cast Broadway touring musicals and grand opera with full chorus and orchestra.