  To an $r$-dimensional subshift of finite type satisfying certain special
properties we associate a $C^*$-algebra $\cA$. This algebra is a higher rank
version of a Cuntz-Krieger algebra. In particular, it is simple, purely
infinite and nuclear. We study an example: if $\G$ is a group acting freely on
the vertices of an $\wt A_2$ building, with finitely many orbits, and if
$\Omega$ is the boundary of that building, then $C(\Om)\rtimes \G$ is the
algebra associated to a certain two dimensional subshift.
