About 18... assuming you were talking about "miles".
san Diego
They are numerous but San Diego International is SFO.
San Diego international airport IATA code SAN is the nearest airport.
From downtown San Diego you cannot see Tijuana; however from some of its suburbs such as San Ysidro and Otay Mesa, you can see the northern areas of the city.
Border each other
San Diego CA. a map of California will help you find out
San Diego International Airport was created in 1928.
Tijuana
It's a 5 mile drive from the San Diego Zoo to the San Diego airport.
The nearest major airport is San Diego International Airport (SAN / KSAN).
No. From both gateways (either San Ysidro or Otay Mesa) you would need to take a cab to get into the Tijuana International Airport.
San Diego, California, USA is just north of Tijuana, Mexico.