Who was it that buried the stupa and temple associated with the Buddha's death?
The Parinirvana (or Parinibbana) Stupa is one of the four holy places declared by the Buddha to be places fit for pilgrimage.
Near the site of the Buddha's death, the stupa possibly housed one-eighth of the Buddha's relics.
No one knows when the stupa and nearby temple were built, but it could have been as early as immediately after his death.
In any case, it was, presumably a centre of pilgrimage during the heyday of Buddhism in India. However, with the "disappearance" of Buddhism, all trace of the stupa and the temple disappeared.
When the remains of the Parinirvana Stupa and Parinirvana Temple, were rediscovered (something like 500 years after they vanished from history), they were apparently buried in a 40 foot high mound of bricks within a dense and thorny forest.
Time covers many things, but it is usually with dust, not bricks. And coverage by bricks does not happen by accident.
I cannot discover any reference to the time when the stupa and temple were buried, to the name of the person who ordered it done, or to any reason why the burial was in 40 feet of bricks rather than in 30 feet or in 60 feet or in any other number of feet of bricks.
Not only were the stupa and temple buried, the whole surrounding area seems to have been declared a "No go" area by means of taboos and superstitions, so that a jungle grew up (or was perhaps even started?) around the sites.
In any case, do these actions not show a deep desire on the part of certain very powerful people to cover all trace of the site and to make it as difficult as possible to reach or even discover?