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The cubic pyrochlore Dy2Pt2O7 was synthesized under 4 GPa and 1000 °C and its magnetic and thermodynamic properties were characterized by DC and AC magnetic susceptibility and specific heat down to 0.1 K. We found that Dy2Pt2O7 does not form long-range magnetic order, but displays characteristics of canonical spin ice such as Dy2Ti2O7, including (1) a large effective moment 9.64 μB close to the theoretical value and a small positive Curie-Weiss temperatureθCW=+0.77 K signaling a dominant ferromagnetic interaction among the Ising spins;(2) a saturation moment~4.5 μB being half of the total moment due to the local<111>Ising anisotropy;(3) thermally activated spin relaxation behaviors in the low (~1 K) and high (~20 K) temperature regions with different energy barriers and characteristic relaxation time;and most importantly, (4) the presence of a residual entropy close to Pauling’s estimation for water ice.