article_snippet.sent: Historians and scientists are divided, but some experts believe the isolated area may have been built to attract people instead imprisoning people, and suggest the isolated area was a summer palace, monastery, or an astronomical observatory.
article_snippet.sent: More in-depth research took place in 2007 with archaeologists discovering clay tablets of human feet, faded coloured drawings on the plaster of the walls, giant gates and fragments of burnt wood.
article_snippet.sent: Archaeologists conducted limited and inconclusive excavations at the site in the 1950s and 1960s .
article_snippet.sent: Scientists were able to use laser mapping to create a 3D image of what the 3.5 hectare plot could have been used for.
article_snippet.sent: Although it is said to be around 1,300 years old, many walls were intact and well preserved with a main structure in the inner courtyard being separated into two parts, covered by a tiled roof walkway supported by 36 wooden columns on stone bases.
article_snippet.sent: a fortress is connected to other land via a small walkway .
article_snippet.sent: The few artifacts unearthed at the site seem to date it to the mid-eighth century .
highlights_snippet.sent: The 3.5 hectare site is estimated to have been built between 744-840 AD .