Complex sentence: Fullerton College is the oldest community college in continuous operation in California, having been established in 1913, when Fullerton was primarily an agricultural community, which specialized in the production of citrus produce.
Split into simpler sentences: Fullerton College is the oldest community college in continuous operation in California, having been established in 1913. At this time, Fullerton was primarily an agricultural community, which specialized in the production of citrus produce.