Emerald Plaza, Mixed-use skyscraper and hotel in Downtown San Diego, United States.

Emerald Plaza is a complex of eight hexagonal towers of varying heights, the tallest rising 30 stories to 450 feet, in downtown San Diego. Its facades alternate bands of green-tinted glass with polished pink granite panels set in custom green aluminum framing. The towers are connected by a 100-foot glass atrium, and their angular rooftops are set at 33 degrees to match the city's latitude.

Construction finished in 1990 under the direction of C.W. Kim Architects & Planners, marking a shift in how San Diego developed its downtown skyline. The project influenced the city's approach to mixed-use development during that period.

Emerald Plaza takes its name from the green-tinted glass of its facades, which developer Sandor Shapery likened to emerald crystals growing from bedrock. The three front towers hold The Westin San Diego, opened in 1991 as the Pan Pacific Hotel under Tokyu Corporation; its 100-foot glass atrium contains a green glass sculpture called "Flying Emeralds".

Emerald Plaza occupies a full block in downtown San Diego's Columbia district, with the hotel in the three front towers and offices in the five rear towers, joined by a 100-foot glass atrium. The complex is a working building, so visitors generally see it from the street or from the atrium lobby rather than touring the towers.

The structure uses a hexagonal design with multiple clustered towers, enabling more rooms with window views while reducing unused interior space. This geometric approach was an innovative solution for maximizing light and optimizing the floor plan.