Complex sentence: Gardiner later owned the Twilight Star Saloon on Kearny Street in the "Barbary Coast, San Francisco, California," area of San Francisco and married a rich American widow and had 2 sons.
Split into simpler sentences: Gardiner later owned the Twilight Star Saloon on Kearny Street in the "Barbary Coast" area of San Francisco. He married a rich American widow and had 2 sons.