California Historical Landmarks are sites designated by the state to recognize their historical significance. These landmarks include buildings, structures, and locations that reflect California's rich cultural heritage, such as the Mission San Juan Capistrano and the Gold Rush-era towns. The California Office of Historic Preservation oversees the designation process, ensuring that these landmarks are preserved for future generations. Each landmark is assigned a unique number and is documented in the California Historical Landmarks program, which helps promote awareness and appreciation of the state's diverse history.