dea1ccde_eople___Life_After_People_Wiki__Predictions
[Time Period] 500 years [Predictions] 
By now, most reinforced concrete structures will crumble away once the iron rebar supports inside them succumb to moisture and the expansion of rust bursts them apart. Without humans to maintain them, it is believed that long standing ancient structures, like the Sphinx at Giza, will have eroded away within 500 to 1000 years.
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Predictions