We present magnetization and Hall effect measurements on the pyrochlore iridate Nd2Ir2O7. Previous muon spin rotation measurements have shown that the system undergoes an unusual transition at T_M = 110 K into a magnetic phase lacking long-range order, followed by a transition at T_LRO = 6 K into a state with long-range magnetic order. We observe a small remnant magnetization when cycling through zero magnetic field at temperatures below T_M. Below T_LRO, this remnant magnetization increases

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... rply, and new hysteresis effects appear at a higher field B_c = 2.5 T, while the Hall resistance develops a non-monotonic and hysteretic magnetic field dependence, with a maximum at B_c and signatures of an anomalous Hall effect. The dependence on field sweep direction demonstrates a non-trivial transition into a magnetically ordered state with properties paralleling those of known spin-ice systems and suggests a spin reorientation transition across the metal insulator transition in the A-227 series.