This image is taken from Google Earth and contains any area known as the San Gabriel Valley (SGV), which is defined most prominently by its geo-physical characteristic of being a valley. Like the San Fernando Valley of the 1980s "Valley Girl" fame or the Central Valley that defines a huge portion of California interior, the SGV is a regional identity. People say they are "from the San Gabriel Valley" or "SGV" and yet this identity covers multiple cities, socio-economic regions, complex and overlapping ethnicities and histories.
If you were to search for the San Gabriel Valley in Google Earth you are taken to a ravine- a point on a map rather than the region which has textual support. Throughout the photo essay for the SGV you can see various visualization that try to capture some aspect of the SGV, but none, it seems to me, are successful in capturing the "valley-ness" of California regions.