  In this note we study CFT$_2$ Virasoro conformal blocks with heavy operators
in the large-$c$ limit in the context of AdS$_3$/CFT$_2$ correspondence. We
compute the lengths of the holographic Steiner trees dual to the $5$-point and
$6$-point conformal blocks using the superlight approximation when one or more
dimensions are much less than the others. These results are generalized for
$N$-point holographic Steiner trees dual to $(N+1)$-point conformal blocks with
superlight weights.
