National treasure with a lid that cannot be opened, ancient magic pot hiding "secret passage mechanisms"

In the 1960s of last century, when Bin County of Shaanxi Province was carrying out maintenance and reconstruction on a section of abandoned city wall, an not very eye-catching porcelain pot was unearthed under the ancient city wall. When this inconspicuous porcelain pot was cleaned up, the experts in ancient ceramics on the scene were very surprised at this quaintly shaped and finely decorated ancient porcelain pot.