From a vista point near the 1,156 long, 130 foot high bridge, completed in 1966, the site of Bagby lies east under, and sometimes exposed beside, the back waters of Lake McClure.

These structures were moved to the historic railhead of El Portal in 1966 prior to the inundation of Bagby by the raising of Exchequer Dam and the expansion of Lake McClure.

First called Johnsonville: Bear Valley had a population of 3,000 including Chinese, Cornish and Mexicans during 1850-60 when Col. John C Fremont's Pine Tree and Josephine mines were producing.

While miners worked nearby streams and veins for gold, George W. Coulter served their needs as merchant and hotel proprietor. His first store, established in 1850, was a tent stocked with merchandise hauled in by pack train. Coulter and the town which bears his name prospered, as Coulterville became the business and social capital of this area.

Started in 1850 by outcast Mexicans from nearby Quartzburg and given the name Hornitos, meaning "little ovens", from the dome like rock and mud bake-ovens being used here by some Germans.

One fourth mile north of Carson Creek, a tributary of Agua Fria, was located Agua Fria, first county seat of Mariposa County in 1850 - 1851 one of original 27 counties in California.

This mortise-and-tenon Greek Revival courthouse, erected in 1854, is California's oldest court of law and has served continuously as the seat of county government since 1854.

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This two-story wood-frame structure in the Greek Revival architectural style was constructed shortly after the fire of 1899 on the site of an earlier lodge building.

General John C. Fremont, 1813-1893. A noted military man, explorer, topographer, senator & businessman, Fremont was also a miner. He settled in Mariposa County living just outside Bear Valley.

After three years of successful operation, Ghirardelli sold his business and moved to San Francisco to devote his full attention to the Ghirardelli Chocolate Company which he had founded in 1853.

The Hornitos jail was probably built in 1851 of heavy stone blocks quarried and transported from nearby hills by Chinese labor. The three-foot-thick walls rest on bedrock. A huge iron ring is embedded in center of floor and other iron rings are affixed to the walls for shackling prisoners.

This building was constructed c. 1855 of native schist rock. It was purchased in August 1873 by the Freemasons of Hornitos Lodge No. 98, and since early 1875, continue to meet here.

This 33 x 26 foot structure was built in 1858 from granite blocks quarried near Mormon Bar at a cost of 14,744.00 by J. O. Lovejoy. It originally had two stories and a gallows at the east end.

Hetch Hetchy Railroad Engine No. 6 is a three truck Shay locomotive, built by the Lima Locomotive Works in 1921

This seventy-acre historic district contains two dozen contributing buildings. Coulterville is California Historical Landmark 332.

Mariposa County High School Auditorium reflects the craftsmanship and skills of its Works Progress Administration workforce. It is Mariposa's best example of the Spanish Colonial Revival style and one of very few buildings in this small town designed by an architect.

The Mariposa Town Historic District is associated with the development of mining, industry and commerce in Mariposa County. It was owned John C. Fremont, a major figure in the exploration of the West and a prominent figure in local and state politics. The district contains sixty-three historic buildings which are among the oldest in California and are good examples of Gold Rush era architecture.

One of the earlier Gold Rush buildings, and one of the last adobe structures left, this general store was established and operated by the Chinese from 1851 until 1926.

Louis Trabucco was born in 1821 and emigrated from Italy in 1847. He opened his first store in Bear Valley in 1856. After becoming successful in his Mariposa mining and business ventures he returned to Italy and married 19 year old Elena Lambruschini in 1860. After returning to Bear Valley they opened stores in Benton Mills, (Bagby), Mount Bullion and Mount Ophir in addition to the Bear Valley store.