  We study K3 surfaces with 9 cusps, i.e. 9 disjoint $A_2$ configurations of
smooth rational curves, over algebraically closed fields of characteristic
$p\neq 3$. Much like in the complex situation studied by Barth, we prove that
each such surface admits a triple covering by an abelian surface. Conversely,
we determine which abelian surfaces with order three automorphisms give rise to
K3 surfaces. We also investigate how K3 surfaces with 9 cusps hit the
supersingular locus.
