Laid-back beach towns. Coastal bluffs. The Anza-Borrego desert badlands. The quaint mountain hamlet of Julian. Wine tasting in Temecula. All this, plus a stop in San Diego, makes for a sweet slice of the SoCal scenic pie. If heat's not your thing, take note: Summer temps in Borrego Springs routinely top 100 F, meaning this is a trip best done in spring and fall.