  In the paper a model problem for the location of a given number $N$ of points
in a given region $\Omega$ and with a given resources density $\rho(x)$ is
considered. The main difference between the usual location problems and the
present one is that in addition to the location cost an extra {\it routing
cost} is considered, that takes into account the fact that the resources have
to travel between the locations on a point-to-point basis. The limit problem as
$N\to\infty$ is characterized and some applications to airfreight systems are
shown.
