The infrared absorption spectra of the water clusters, (H2O)(n) with n = 2-6, have been observed in solid neon matrices. In the bonded OH stretching region we have detected an absorption peak due to the monocyclic water hexamer at 3329 cm(-1), which had been detected earlier only in liquid He droplets and para-hydrogen matrices. This Letter presents the first spectroscopic observation of the monocyclic water hexamer in solid rare gas matrices. (c) 2006 Elsevier B.V. All rights reserved.