Founded by Fernando Martin on Sep. 20, 1818 as an Asistencia to Mission San Diego de Alcalá.

California Missions Foundation about the Asistencias.

The address of the former Asistencia is:
23013 CA-79, Santa Ysabel, CA 92070.
The original Adobe building was neglected and fell into into disrepair. In year 1924 the Church of San Juan Bautista (Saint John the Baptist) was erected on the site of the original Santa Ysabel Asistencia.

Official web site of Asistencia Santa Ysabel is mostly only a source of a contact for the parish. Visiting information can be seen on this image on Google Maps Image. On the premises is a small museum, and even a gift shop, but open only on selected days of the week. In the Museum visitor can find a detailed leaflet with the history of the Asistencia and its buildings. The original inhabitants call themselves Lipay (the People) and belong to a Yuman language family. First Friar to visit the vicinity was Fr. Juan Mariner in year 1795.

The historic bells of the mission were apparently stolen in year 1926. One of them was bought for the Asistencia from a much older Misión de Nuestra Señora de Loreto Conchó (Mission Loreto), founded October 25, 1697 by Jesuits in Baja California. In year 1993 a new bell was made by Ed and John Schwaesdall and donated in honor of the Mission's 175th anniversary. Read about the details of this strange case on the Wikipedia pages.

Wikipedia page of Asistencia Santa Ysabel.