Casa de Oro is considered the gateway to Mt. Helix, Ca The neighborhood of Casa de Oro is considered the gateway to Mt. Helix and is part of the unincorporated portion of the County of San Diego. The Mt. Helix/Casa de Oro Area generally consists of commercial and high-density residential core along Campo Road and low-density high-income housing to the north up the slopes of Mt. Helix. To the east, the area gradually becomes more rural and agricultural in the vicinity of Jamacha Road. This community appears to be in a healthy state, and the main threat of change comes from pressures for higher-density residential development in the Mt. Helix Area, and the rural agricultural area near Jamacha Road. Picture from City-data.com Existing residential development varies widely in the Valle de O... 08/12/2010