California Citrus State Historic Park preserves the grove, packing houses, and the history of the navel orange industry that Riverside pioneered in the 1870s. The park tells the story of how two Brazilian navel orange trees, planted in Riverside in 1873, sparked an agricultural revolution that shaped modern California. Walking trails wind through fragrant working groves; come in spring when the blossoms are out and the scent is extraordinary. The restored packing house gives a clear picture of how the citrus industry operated at its peak.