Irradiation of the aryl-substituted norbornan-2-ones 6 and 7 at 254 nm furnishes the triquinanes 16 and 17(from 6) and 18(from 7)via tandem Norrish Type 1 reaction and intramolecular arene–alkene meta-photocycloaddition of the intermediate unsaturated lactols 12 and 13, respectively.