Water tunnel that was carved under the City of David in Jerusalem in ancient times. it dates from the reign of Hezekiah, time when Jerusalem was preparing for an impending siege by the Assyrians, led by Sennacherib.

Kane Khanh | Archeaology
March 25, 2024

Water tunnel that was carved under the City of David in Jerusalem in ancient times. it dates from the reign of Hezekiah, time when Jerusalem was preparing for an impending siege by the Assyrians, led by Sennacherib.

I believe that one of the most amazing things one can see on this planet is Hezekiah’s Tunnel in Jerusalem. There are few places on earth that bring ancient history to life as well as this remarkable hand-chiseled tunnel. Let’s see why.

Judea and the Assyrians

Around 2,600 years ago, the Assyrian Empire was on a conquering streak. At the time, it was the largest kingdom in history, and the little Kingdom of Judah was no match, losing most of its territory in waves of attacks. The legendary Judean King Hezekiah was forced to humble himself before the Assyrians and pay them an inordinate amount. He even sawed off the golden doors from the Holy Temple and had them shipped to Assyria, in the hope that whatever little remained of his kingdom would be left alone.1

But the Assyrians were not satisfied. An army of nearly 200,000 amassed at the outskirts of Jerusalem, threatening to snuff out the last morsel of Jewish independence. Sennacherib, king of Assyria, sent a Jewish renegade to curse the Jews and insult their King in Hebrew,2 which struck terror into the Israelites’ hearts.3 It looked like their case was hopeless. Hezekiah turned to G‑d in prayer,4 and in response, the prophet Isaiah came with a Divine message:

The three millennia old tunnels under ancient Jerusalem (x-post  /r/papertowns) : r/engineering

Therefore, so has the L‑rd said concerning the king of Assyria: “He shall not enter this city; neither shall he shoot there an arrow, nor shall he advance upon it with a shield, nor shall he pile up a siege mound against it.”5

In what remains one of the great mysteries of history, the mighty Assyrian army perished overnight on the foothills of Jerusalem on the first night of Passover, and Judea was miraculously saved.

Hezekiah’s Tunnel

Anticipating a devastating attack by the Assyrians, King Hezekiah fortified the walls of Jerusalem and bolstered its defenses. But one thing troubled him in particular: Jerusalem’s main water source lay outside the city walls. Not only would they lose access to their water supply, but the enemy would enjoy an unlimited amount of water for its troops. Under such circumstances, Jerusalem was in the gravest danger.

According to the Biblical story, Hezekiah launched one of the most technologically complex operations in all of ancient history. He decided to reroute the water source into the city limits, thereby securing his own water supply whilst depriving his enemy access. But how could this be done? Only by boring a lengthy tunnel through solid rock!

Here is how the incredible project is described in the Book of Chronicles:

Hezekiah saw that Sennacherib had come, and his face was directed to wage war against Jerusalem.

So he took counsel with his officers and his mighty men to stop up the waters of the fountains that were outside the city, and they assisted him.

And a large multitude gathered and stopped up all the fountains and the stream that flowed in the midst of the land, saying, “Why should the kings of Assyria come and find much water?”

He, Hezekiah, stopped up the source of the waters of the upper Gihon, and he led them straight down on the west to the City of David, and Hezekiah prospered in all his works.6

Some 500 years later, the Romans laid ruin to Jerusalem. The city became virtually uninhabited, and gradually the tunnel became hidden. The astonishing feat could only be read about in the Bible: the legendary tale of a heroic king who made water flow through rock.

A Great Discovery

Then in 1838, American researcher Edward Robinson discovered the tunnel and conducted the first modern study. The work of researchers over the years has revealed that this accomplishment was even more astonishing and breathtaking than anyone could have imagined. It turned out that the full length of the water tunnel is approximately 534 meters (1,752 feet) —over a third of a mile—through solid rock!

One of the most amazing discoveries was that the tunnel had been cut by two groups of workers approaching each other from opposite ends. How could they have been able to meet up at the exact same spot without sophisticated, modern equipment? To this day, no one has been able to provide an adequate explanation for how they could have navigated through the rock with such precision.

Another mystery is how the workers had had enough oxygen to breathe, and for their lanterns. The long tunnel has virtually no inlets for air or light. How could they have breathed 150 feet into a mountain, many hundreds of feet from the entrance, without becoming asphyxiated?

Moreover, when the tunnel was fully scoped out, researchers were astonished to discover that the entire length of more than half a mile is almost perfectly level. The height difference between the entrance and the exit is hardly more than one foot. It is nearly impossible to imagine how this could have been accomplished without modern-day equipment.

Blast from the Past

In 1880, researchers discovered that the workers had not only left a record of their efforts, but provided vital insight into how the project was undertaken. For the first time, it became clear that two teams were working towards each other from either end. It even records the moment when, on the day the tunnel became complete, each group could hear the other approaching. Reading their inscription, it is hard not to sense their overwhelming excitement at having pulled it off. Here is what they inscribed (with missing words in brackets):

The tunneling [was completed]. This is the narrative of the tunneling: While [the stone-cutters were wielding] the picks, each toward his co-worker, and while there were still three cubits to tunnel through, the voice of a man was heard calling out to his co-worker, because there was a fissure in the rock, running from south [to north]. On the (final) day of tunneling, each of the stonecutters was striking (the stone) forcefully so as to meet his co-worker, pick after pick. Then the water began to flow from the source to the pool, a distance of 1,200 cubits. And 100 cubits was the height of the rock above the head of the stone-cutters.

Shortly after its discovery, this remarkable inscription was chiseled out and removed by the Ottoman Turks, causing some damage. It is currently housed at the Istanbul Archaeological Museum. To this day, that inscription remains one of the most significant finds of ancient Hebrew writing. It gives testimony to a unique moment in history, and provides a compelling voice for the people who participated in this momentous project.

Archeologists have debated for decades whether the tunnel is indeed the one described in the Bible as constructed by Hezekiah. In 2003, a radiometry test was conducted by researchers from the Hebrew University in Israel and Reading University in England, and they set the tunnel in the timeframe of Hezekiah. The matter is now pretty much settled: our tunnel is indeed the one constructed by Hezekiah.7

You Can Visit the Tunnels

Any visitor to Jerusalem can see this historical site for themselves. In an immersive experience that allows one to feel the all-encompassing history, the visitor can descend into the tunnel, and walk – partially wading in knee-deep water – through the tunnel. One can see all the markings from the pickaxes that made their impression on the stone millennia ago. One can stand at the exact spot where the two groups of workers finally broke through and imagine their excitement at coming together.

The tunnel culminates in a pool, called the Shiloach Pool, which is where the priests would immerse before ascending to the Holy Temple.

What Did the Rabbis Say?

Having accomplished such an amazing feat, Hezekiah’s tunnel received undiluted acclaim, right? Well, not so fast.

The Talmud8 lists the stopping up of the Gihon river as something that the rabbis did not approve of. Rashi explains that the rabbis felt that “Hezekiah should have trusted the Holy One Blessed is He, who promised ‘I will protect this city, to save it.’ ”9 As it turned out, there was no need for the tunnel because the whole Assyrian army was wiped out anyway.

Nevertheless, other classical sources state that Hezekiah’s “mind aligned with that of the Omnipresent,”10 and is listed as something for which Hezekiah was praised.11 In fact, in the Hoshanot service on the seventh day of the festival of Sukkot we invoke Hezekiah’s righteousness. Among the deeds referenced is how he stopped up the streams of water in the face of the Assyrian “desecrater.”

Parting the Waters of the City of Jerusalem in the Siloam Tunnel of King  Hezekiah | Ancient Origins

The great Sephardic scholar, Rabbi Chaim Yosef David Azulai (the Chida, 1724-1806), suggests that both positions can be reconciled.12 The sages in the times of Hezekiah did indeed mostly disapprove of his actions, but G‑d nevertheless approved of what he did, since he had a valid reason for doing so. The Talmud advances the view that given the majority of the sages at the time were against the idea, Hezekiah should have heeded their advice. It can still be true – as the other sources say – that having gone with his own judgment in this instant, his decision was met with Divine favor.