In the southern part of the Mother Lode region lies Bear Valley, a once busy mining town 12 miles northwest of Mariposa on Highway 49. It was headquarters for John C. Fremont's gold mining empire in the mid-1850s. At its peak, approximately 3000 people lived here. 

During the late 1850s the long main street (now Highway 49) was lined on both sides with saloons, restaurants, hotels, and other businesses. A few remaining buildings from this time are the Simpson & Trabucco Store, the IOOF Hall, and the Mrs. E. Trabucco Store.

Louis Trabucco, a 25 year old immigrant from northern Italy, arrived in New York in 1846. In 1850 he joined a wagon train to California first settling in Hornitos, 11 miles southwest of Bear Valley. He moved to Bear Valley in 1852 and worked in the mines. He later opened his first store in town. In 1869 his store was destroyed by fire and Louis bought this building. It housed his store and home. His merchandising business was successful and he opened three other stores in Mariposa County, Benton Mills, (now Bagby), Mount Bullion, and Mount Ophir. 

After Louis died in 1883, his wife, Elena, continued to run the the store for many years. The store became known as the Mrs. E. Trabucco Store. The store continued operation until 1912. Currently a great-grandson of Louis and Elena lives here.