San Dimas is a community whose roots go deep into the nineteenth century. The first Americans arriving in the locality presently known as San Dimas were a band of explorers headed by Jedediah Strong Smith, who camped at a Cienega (marshy area), later called Mud Springs, in 1826. A monument on E. Arrow Highway marks the approximate location.
In 1837 two Spanish Dons, Señor Ignacio Palomares and Señor Ricardo Vejar came into these vast semi-arid and wilderness pastures. Their immense land grant was christened Rancho San Jose and was a range for vast herds of cattle. The favorite mythical story is that outlaws operating from inaccessible haunts in the San Dimas Canyon, often made raids on these cattle. Some claim they (the outlaws) were renegade Indians. Señor Palomares, who had come from Sonora, Mexico, where there had been a village called San Dimas, angrily referred to Dismas, the repentant thief of the cross. The story has it that Don’s allusion suggested a name for the canyon – “San Dimas Canyon.” The City of San Dimas assumed its name from the canyon.
An era of droughts and financial reverses resulted in the break-up of the California Rancho. Meanwhile, the Mud Springs had become the location for a station of the Banning Stage Line, with Dennis Clancy in charge. In the 1860s, the Clancy family were the first American residents and their two children the first to be born here. The Mud Springs site on Palomares Street has long been dry.
The Teague family, the first farmers to settle in this area, came in 1878. They leased large acreage upon which they raised grain until the citrus era dawned, and San Dimas became the “Queen of the citrus belt” in Southern California. With the growth of the Los Angeles metropolitan area, the citrus groves of the early 1900s have, in turn, given way to urbanization, and in 1960 (August 4) the citizens of San Dimas incorporated as a city so that they might chart the course of their development more effectively. Since its incorporation in 1960, the unprecedented growth of San Dimas has transformed the City from a primarily rural area to a well-balanced community offering industrial, commercial, and residential living. The completion of new freeways (Foothill and Orange Freeways) will benefit the City since it is in a fortunate position to take advantage of this easy access to markets. In addition to the 1,700 acre Frank G. Bonelli Recreational Area, which lies within the City boundaries, there are many parks such as San Dimas Canyon Park, a city-owned golf course (San Dimas Canyon Golf Club), and over 27 miles of equestrian trails for riding. The city services include an extensive recreational program for youth and senior citizens, and the City boasts a new modern City Hall, with excellent provisions made for County Sheriff and Fire Departments, along with a beautiful Los Angeles County Library and Engineering Regional Office. A bright future lies ahead for San Dimas. Its growth is based upon a solid foundation, and the projections are that in a decade, its population will reach 40,000, and its reputation as a City that tires “to preserve the western spirit” will grow with the population growth.