Burying Religion?"Remains of buried temple may mark point of religious transformation when prehistoric society shifted from worshipping landscape to the Sun."That ia about new discoveries near Stonehenge.
Another instance of burial of a site for unknown reasons is Göbekli Tepe:
"Around the beginning of the 8th millennium BCE Göbekli Tepe ("Potbelly Hill") lost its importance. The advent of agriculture and animal husbandry brought new realities to human life in the area, and the "Stone-age zoo" (Schmidt's phrase applied particularly to Layer III, Enclosure D) apparently lost whatever significance it had had for the region's older, foraging communities. But the complex was not simply abandoned and forgotten to be gradually destroyed by the elements. Instead, each enclosure was deliberately buried under as much as 300 to 500 cubic meters (390 to 650 cu yd) of refuse consisting mainly of small limestone fragments, stone vessels, and stone tools. Many animal, even human, bones have also been identified in the fill. Why the enclosures were buried is unknown, but it preserved them for posterity."