Important early map of San Diego and San Blas, based upon the surveys of Juan Pantoja. Pantoja was a captain plying the Manila trade for Spain in the late 18th Century. The base of operations was San Blas. Pantoja made several supply runs north along the coast, stopping in San Diego, Monterrey and San Francisco among other places, to supply the missions and make surveys. Before he could transmit his work to Madrid, he apparently shared his work with La Perouse, who was then exploring the Pacific in the wake of Cook's monumental voyages. Ironically, both men died before their works were published. From the first french edition of atlas. La Perouse probably never actually entered into the harbor and relied solely on Pantoja's manuscript charts for his information. He certainly did not conduct any surveys of the Bay. The map shows the Presidio, several ranchos and the landing prominently described by Dana in 3 Years Before The Mast. This is the earliest obtainable printed map of San Diego, preceded only by rare maps by Dalyrmple and a few other equally unobtainable works. San Blas was the primary Spanish depot on the west coast of Mexico. A fine example of a seminal map of San Diego.