For z1, z2, z3 Zn, the tristance d3(z1, z2, z3) is a generalization of the L1-distance on Zn to a quantity that reflects the relative dispersion of three points rather than two. A tristance anticode Ad of diameter d is a subset of Zn with the property that d3(z1, z2, z3) d for all z1, z2, z3 Ad. An anticode is optimal if it has the largest possible cardinality for its diameter d. We determine the