California is the most populous state in the United States, and he third largest by area. California is the second most populous sub-national entity, behind only São Paulo, Brazil. It is located on the West Coast of the United States, and is bordered by Oregon to the north, Nevada to the east, Arizona to the southeast, the Mexican state of Baja California to the south, and the Pacific Ocean to the west. From the amusement parks and sunny beaches of Southern California to the rugged cliffs and deserted beaches on the Northern Coast and everything in between, there is no end to all the things you can experience on a California tour.

In the middle of the state lies the California Central Valley, bounded by the coastal mountain ranges in the west, the Sierra Nevada to the east, the Cascade Range in the north and the Tehachapi Mountains in the south. The Central Valley is California's agricultural heartland and grows approximately one-third of the nation's food. Divided in two by the Sacramento-San Joaquin River Delta, the northern portion, the Sacramento Valley serves as the watershed of the Sacramento River, while the southern portion, the San Joaquin Valley is the watershed for the San Joaquin River; both areas derive their names from the rivers that transit them. With dredging, the Sacramento and the San Joaquin Rivers have remained sufficiently deep that several inland cities are seaports. The Sacramento-San Joaquin River Delta serves as a critical water supply hub for the state. Water is routed through an extensive network of canals and pumps out of the delta, that traverse nearly the length of the state, including the Central Valley Project, and the State Water Project. Water from the Delta provides drinking water for nearly 23 million people, almost two-thirds of the state's population, and provides water to farmers on the west side of the San Joaquin Valley. The Channel Islands are located off the southern coast.

California climate varies from Mediterranean to subarctic. Much of the state has a Mediterranean climate, with cool, rainy winters and dry summers. The cool California Current offshore often creates summer fog near the coast. Further inland, one encounters colder winters and hotter summers.

Northern parts of the state average higher annual rainfall than the south. California's mountain ranges influence the climate as well: some of the rainiest parts of the state are west-facing mountain slopes. Northwestern California has a temperate climate, and the Central Valley has a Mediterranean climate but with greater temperature extremes than the coast. The high mountains, including the Sierra Nevada, have a mountain climate with snow in winter and mild to moderate heat in summer.

The two most prominent rivers within California are the Sacramento River and the San Joaquin River, which drain the Central Valley and flow to the Pacific Ocean through San Francisco Bay. Two other important rivers are the Klamath River, in the north, and the Colorado River, on the southeast border.

Disneyland and Seaworld are family friendly places to enjoy a California vacation. Neighborhoods in LA are so outstanding that many have their own reputation that overshadows that fact that they are within a larger city. Hollywood, for example, has the Walk of Fame, and is home to the big movie studios.