  Theoretical proposals for spin ice analogs based on nanostructured
superconductors have suggested larger flexibility for probing the effects of
fluctuations and disorder than in the magnetic systems. In this work, we unveil
the particularities of a vortex ice system by direct observation of the vortex
distribution in a kagome lattice of paired antidots using scanning Hall probe
microscopy. The theoretically suggested vortex ice distribution, lacking long
range order, is observed at half matching field (H_{1}/2). Moreover, the vortex
ice state formed by the pinned vortices is still preserved at 2H_{1}/3. This
unexpected result is attributed to the introduction of interstitial vortices at
these magnetic field values. Although the interstitial vortices increase the
number of possible vortex configurations, it is clearly shown that the vortex
ice state observed at 2H_{1}/3 is less prone to defects than at $H_{1}/2$. In
addition, the non-monotonic variations of the vortex ice quality on the lattice
spacing indicates that a highly ordered vortex ice state cannot be attained by
simply reducing the lattice spacing. The optimal design to observe defect free
vortex ice is discussed based on the experimental statistics. The direct
observations of a tunable vortex ice state provides new opportunities to
explore the order-disorder transition in artificial ice systems.
