This paradox mystical holiness of the place can be explained. The most plausible seem to be the following, there is an increased level of radiation on the Acropolis hill, and so the smart birds feel it and do not attend.
Göbekli Tepe. Göbekli Tepe is an archaeological site of a temple in Southeastern Turkey and has been dated back to 9500 - 8000 BCE. This date was discovered by carbon dating old tools found during excavations. This building is in fact the oldest structure on earth that we have found to date.
The final difference between the two sacred spaces might be that Stonehenge has remained largely undisturbed in its structure since its creation from 3,200 to 1,500 BCE, while the Parthenon, built from 447 to 432 BCE, was actually built over a temple that previously been burned down by the Persian Army around 480 BCE ( ...
The Romans built The Pantheon in 126 A.D. as a “temple to all gods.” The columned portico, triangular pediment, and large, domed rotunda became the design template for important landmarks worldwide.
The earliest masonry dome, the Pantheon, was so heavy that engineers carved intricate shapes, called coffers, along the walls to reduce the weight of the enormous structure. They also gouged a hole, called an oculus, at the top, which created a daily light show for which the Pantheon is still famous.