Balboa Park, San Diego Platt/Whitelaw was retained by the City of San Diego to remove specified barriers to accessibility at Balboa Park, a National Historic Landmark. In addition to the requirements of current ADA and California Title 24 regulations, most of the structures are historical buildings requiring sensitivity to the structures and the location. Platt/Whitelaw made significant accessibility improvements to Museum of Man, Timken Gallery, Hall of Nations, Casa De Balboa, and Morley Field, including interior and exterior ramps, handrails, improved path of travel, and restroom renovation.