Years on TV:
1952-2009 (an earlier radio show, pictured, started in 1937)
After leaving its roots in radio, the long-running TV show had a cast that included eventual "Heroes" star Hayden Panettiere and actor Christopher Walken. See who else got their start on "Guiding Light.
What started as a tale about a widowed reverend who kept a light on his desk as a sign of comfort evolved to include marital conflicts, class distinctions and feuding families. The TV show, which dropped the "The" from its name in the 1970s, is credited with being the longest-running American soap opera.