[4] The original purpose of the structure is unknown, though the adobe was located in the center of the Mission's orchards and surrounding vineyards.

In 1846 the Pío Pico government sold Eulogio de Celis the secularized Mission lands, nearly the entire San Fernando Valley, as the Rancho Ex-Mission San Fernando, which included the Pico Adobe.

Pio Pico sold his southern half of the San Fernando Valley to Isaac Lankershim in 1869.

In 1874, the heirs of Eulogio de Celis sold their northern half of Rancho Ex-Mission San Fernando lands to northern Californians: California State Senator Charles Maclay and his partners George K. Porter, a San Francisco shoe manufacturer, and his brother Benjamin F. Porter.

Some invaders dug up the floors and knocked down walls in search of fabled buried gold and 'treasure.

'[3] In 1930, Mark Raymond Harrington, curator of the Southwest Museum, purchased the abandoned property from the heirs of the Lopez family.

I regard the main building as having been built in the Mission period - probably early 1830s, the wings possibly added by the Picos.

The adobe is also used for the Historical Society's monthly meetings, weddings, receptions, breakfasts, dinners, and picnics.

The Pico Adobe has been listed as a historic building at the city, state, and national level as follows: