  Remote spatial indistinguishability of identical subsystems as a direct
controllable quantum resource at distant sites has not been yet experimentally
proven. We design a setup capable to tune the spatial indistinguishability of
two photons by independently adjusting their spatial distribution in two
distant regions, which leads to polarization entanglement starting from
uncorrelated photons. The amount of entanglement uniquely depends on the degree
of remote spatial indistinguishability, quantified by an entropic measure
$\mathcal{I}$, which enables teleportation with fidelities above the classical
threshold. This experiment realizes a basic nonlocal entangling gate by the
inherent nature of identical quantum subsystems.
