This is a Curt Teich postcard, of which the numbering scheme is known and translates into the date. The number at the right bottom here, 1A-H499, indicates the year 1931, with the "H" meaning card is a "linen" card. This downtown aerial view of San Diego from the Atchison, Topeka and Santa Fe tracks near San Diego Bay to Balboa Park shows the El Cortez Hotel prominently in almost the center of the card. This hotel (later condominiums) was the tallest building in San Diego until 1963. Behind and to the left of the hotel is the Cabrillo Bridge built for the Panama-California Exposition of 1915, as were the most prominent buildings just to the right of the hotel in the background, the California Building and Tower.
