It surprised Hao Ren, as the entrance to Hades was not only in the suburbs not far from Rome, but it was also exposed in the open without any form of concealment and disguise. It could even be considered as a landmark. Even the farmers who lived nearby knew of its existence. But they only knew that it was a scary place. They had no clue that it led to the abode of the dead as described in myths and legends.
It was a cave in the suburbs, where there were many horror legends related to it.