The City of San Diego is located along the southern shores of the Californian coast. It has a population of 1, 419, 516, which comprises the majority of the labour force as well. This makes San Diego the second-largest city in California and the 8th largest in the United States.

Air access to numerous international markets is provided by the San Diego International Airport. Road linkages to other cities in California, the rest of the United States, as well as Mexico are accessed through four major interstate freeways and six state highways that cross the city. Road access is relatively uncongested which allows for the rapid transit of goods to markets. The Port of San Diego provides maritime access and allows the importation and shipment of various cargo from overseas markets. Freight Rail Service by the Burlington Northern Santa Fe Railway allows cargo transport by train to the rest of the United States and Mexico. San Diego also functions as a transport hub for long-haul trucks.

Because of the relative proximity by air, land and sea, among the heavy industries located in San Diego is that of International Trade and Transport, Manufacturing, and the Military Industries. The Heavy Industrial Complexes, particularly warehousing and manufacturing industries are concentrated along the waterfront of San Diego Harbor. This area contains the Port Authority of San Diego, numerous military-based businesses, and the U.S. Naval Base located in San Diego. Other heavy industrial sites may be found in Harbor Drive, which are mostly warehouses and storage facilities.

References:

https://www.bls.gov/eag/eag.ca_sandiego_msa.htm

https://www.sandiego.gov/economic-development/sandiego/location

https://www.sandiego.gov/economic-development/sandiego/facts

https://www.sandiego.gov/sites/default/files/legacy//planning/community/profiles/pdf/cp/cpblpelanduse.pdf