From the Guidebook:
This imposing building is
an excellent example of California's Mexican-era architecture.
With Indian labor, Petronilo Ríos built the two-story
adobe about 1846 as his residence and the headquarters
for his sheep and cattle operations. Named 'Caledonia'
in the 1860s, it served as a hotel and stop on the stage
route between Los Angeles and San Francisco until 1886.
Restoration was begun in 1968 by the Friends of the Adobes.