This is another must visit city in California. The splendid beaches facing the vast coastlines are the perfect mood setters in San Diego. As you explore the city you get to learn finer nuances of the Mexican culture. Located on the coast of the Pacific Ocean adjacent to the Mexican border, San Diego is considered as the birthplace of California. It's mild year-round climate is what makes it filled with visitors round the year. It was earlier the home to Kumeyaay people and the first place visited by Europeans. In 1850 San Diego became part of the United States while including California in the union. University of California in San Diego and the affiliated UCSD Medical Center are the major hubs for research in biotechnology.