Excavators recently uncovered a "mysterious and impressive" ancient tunnel in Jerusalem, not far from archaeological sites tied to the biblical Kingdom of Judah.The discovery was announced by the Israel Antiquities Authority (IAA) in a May 14 statement.The tunnel was found near Kibbutz Ramat Rachel, an archaeological site tied to the biblical-era Kingdom of Judah, according to previous IAA excavations.TOURISTS WALK PILGRIMAGE ROAD FROM JESUS' ERA FOR FIRST TIME IN 2,000 YEARS: 'DEEPLY SIGNIFICANT'The rock-hewn tunnel is about 164 feet long and was found ahead of construction on a new residential neighborhood north of Ramat Rachel.The tunnel is around 16 feet tall and roughly 10 feet wide — and officials note that the rock-cutting "was executed meticulously.""The tunnel itself was discovered filled with layers of soil that had accumulated over hundreds, perhaps even thousands, of years," the IAA said."It is clear that whoever carved this tunnel invested tremendous effort [and] careful planning, and possessed the capabilities and resources necessary to achieve this goal."FORBIDDEN PASSAGE? SECRET MEDIEVAL TUNNEL FOUND BENEATH ANCIENT PAGAN GRAVES, ARCHAEOLOGISTS SAYExcavation directors Sivan Mizrahi and Zinovi Matskevich told the IAA the discovery was unexpected."We were excavating in relatively rocky and exposed terrain when suddenly we discovered a natural karstic cavity," the pair said in a joint statement."To our amazement, as the excavation progressed, this cavity developed into a long tunnel. Parts of it are still collapsed, so the tunnel has not yet revealed all of its secrets."In 2020, IAA excavations near Ramat Rachel revealed seal impressions and structures tied to the Kingdom of Judah, indicating that "governmental activity took place in the area," the organization said at the time.CLICK HERE TO SIGN UP FOR OUR LIFESTYLE NEWSLETTERNo evidence that's been uncovered so far, however, directly connects the newly discovered tunnel to the Kingdom of Judah or the biblical era — and the age of the tunnel is unknown."The tunnel lies only a few hundred meters, as the crow flies, from two significant ancient sites — a public building from the Iron Age (First Temple period) in the Arnona neighborhood, and Tel Ramat Rachel, where settlement remains dating from the Iron Age through the Islamic period have been documented," Mizrahi and Matskevich said.Though the purpose of the tunnel remains unclear, researchers theorize it may have been carved to reach a chalk layer used for quarrying building stones or producing lime."Possible evidence supporting this interpretation includes a shaft carved into the tunnel’s ceiling, which may have been used for ventilation, as well as quarrying debris discovered on the tunnel floor — although this interpretation, too, remains uncertain," the IAA said.CLICK HERE FOR MORE LIFESTYLE STORIESExperts have ruled out the possibility that the tunnel was part of an ancient water system, and some posit the site may have been abandoned before construction was completed."Alternatively, the findings may indicate that the quarrying and construction of the tunnel were never completed, and therefore its intended purpose and nature remain unknown," the IAA says.Amit Re'em, a Jerusalem district archaeologist at the IAA, said the find "joins many others being uncovered every day, hour by hour, throughout the city.""The archaeologists and researchers of the Israel Antiquities Authority are constantly at work, because this city never ceases to surprise," said Re'em."Usually we have explanations for the discoveries we uncover, but sometimes, as in this case, we stand astonished and amazed."TEST YOURSELF WITH OUR LATEST LIFESTYLE QUIZFox News Digital reached out to the IAA for comment.