The Agua Mansa Valley is located on the south side of Slover Mountain. The valley was in length; its width varied between and, the variance depending on the river that flowed through the valley. The area was used as farmland, divided into at least one hundred fields, owned by separate farmers. The valley's lower end included a Frémont's cottonwoods riparian forest owned by Rubidoux, while the upper end was a sandy plain that extended to the borders of present-day San Bernardino.
History
In 1845, Don Juan Bandini donated parts of his land grantRancho Jurupa to a group of Mexican colonists from Abiquiú in Santa Fe de Nuevo México — on the condition that they would assist in protecting his stock from local Indian raids. Ten of these families moved to on the "Bandini Donation" on the east side of the Santa Ana River, forming the village of La Placita, while a second group colonized the west side of the river, forming the town of Agua Mansa. The group that formed Agua Mansa was led by Don Jose Tomas Salajar, and included Cristobal Slover and Louis Rubidoux. After the adobe church built in La Placita in 1852 collapsed in quicksand, a new church was built in Agua Mansa. Completed in 1853 and dedicated to San Salvador, the church survived through the Great Flood of 1862. The parish, which included Agua Mansa and La Placita, became known as San Salvador de Jurupa, and was the first non-mission parish in Southern California. The chapel's bell now hangs at the Glenwood Mission Inn. The town prospered for almost 20 years until the 1862 floodingswept away many of the adobe buildings, leaving the area strewn with sand and gravel. Though the town was rebuilt on higher ground, its prosperity did not return. Built in 1870 in Agua Mansa, the Jensen Alvarado Ranch is a California Historical Landmark and is listed on the National Register of Historical Places. Its vineyard produced and sold thousands of gallons of wine each year.
Agua Mansa Pioneer Cemetery
Agua Mansa is designated California Historical Landmark. The marker is located at Agua Mansa Pioneer Cemetery, the only site that remains of the once flourishing town. The first burial occurred in 1852, and the last occurred 111 years later in 1963. In 1955, a descendant of the original Agua Mansa families established "Friends for the Preservation of the Agua Mansa Pioneer Cemetery" and the volunteers of this group refurbished the cemetery, fenced it off and added a gate. In 1967, the cemetery became a branch of the San Bernardino County Museum after its acquisition by San Bernardino County. It has a museum and chapel, and tours are available. Records of who is buried in the cemetery are incomplete but about 1,400 names have been identified out of a total of 2,000 estimated burials. Only a few grave markers remain today. The earliest known interment was that of Louis Rubidoux, who came to California in 1844 and bought the Jurupa Rancho near today's City of Riverside. Another burial was that of Cornelius Jensen in 1886; Jensen was a Danish sea captain who established a store at Agua Mansa before moving to part of the Robidoux ranch. Jensen's wife, Mercedes Alvarado, is also buried in the cemetery along with other members of her family. Lorenzo Trujillo, the original patriarch of the community, is also believed to rest somewhere in a grave that long ago lost its marker. Isaac Slover, a mountain man and bear hunter who came to California in his old age, is also buried in the cemetery.
California Historical Landmark Marker
This historic site marks the resting place of the pioneers of the Agua Mansa area which was started about 1840. The preservation of this cemetery began in 1951. Erected 1961 by Jurupa Palor No. 296 Native Daughters of the Golden West.
