San Ysidro is a city in San Diego County in California along the border between the United States and Mexico.
It has a population of approximately 90 thousand people and
is home to the world's busiest land crossing between two
countries. (The most recent figure I have found so far is from 1998, during which there were 90 million border crossings.)
The name of this city is pronounced San Ee-Seed-Row and is of Spanish origins. And the city's look and feel does have a distinctly Spanish influence. But the rest of us here in San Diego pronounce it San Ee-Skid-Row because it is one of the most impoverished portions of San Diego County. Property values in the region are at best in the $150-175K range, and that's for 3 or 4 bedroom, 2 story homes. Most of which you'll find look more like prisons than humble abodes because they're equipped with bars on the windows and various references to security alarm agencies posted in their front windows. But hey, some people enjoy living in poverty and having people shot to death whilst driving down their streets. Go figure.
The scenery and quality of life will appear just a little bit better than San Ysidro's neighboring city: the infamous Tijuana, Mexico. You should have equal reservations about walking the streets alone at night or leaving your car unattended regardless of which side of the border you're on, though.