Archaeologists say they were not particularly shocked when a 100-kilogram (220-pound) fragment of rock broke off the Western Wall in Jerusalem on Monday, narrowly missing a worshipper below.
The question is whether any other pieces of rock are likely to fall off the Kotel, at least in the foreseeable future.
Yes, the 1-meter-thick (3.3 foot) bricks in the bottom courses of the 2,000-year-old wall are eroding. That is what happens to all structures exposed to sun and weather, says Prof. Simon Emmanuel of the Hebrew University’s Institute of Earth Sciences.
Some of these stones will fail and pieces of them will fall off, over time – and nobody can say when. So while worshippers could be in some danger, at least the wall itself is not. It is there to stay, he reassures.
“I never saw a thing like that before. It was very surprising,” says Prof. Eilat Mazar of the Hebrew University, a third-generation expert on Jerusalem archaeology. “The Western Wall is very stable,” she adds.
The Kotel may be stable as, well, a rock. But all structures on the surface of the planet – man-made or natural – experience weathering, Emmanuel explains. That is the nature of matter. Rocks have fallen off the wall before, and will again.
“This will happen; it’s a big wall,” says Emmanuel. “What happened was a catastrophic failure of the rock. It will happen in any monument of that size, in time. It isn’t something that is necessarily preventable. The fate of every man-made structure – and natural ones, too – is to erode away.”
As for the latest piece of rock to fall, its fate is to be stored safely in the offices of the Western Wall Heritage Foundation, Chief Rabbi Israel Lau decided on Tuesday after visiting the Kotel in the company of Culture Minister Miri Regev and Western Wall Rabbi Shmuel Rabinovitch.
The minister, for her part, took the opportunity to suggest that the Israel Antiquities Authority conduct another survey of the state of the stones.
Meanwhile, the rate at which the brick stones are deteriorating is so slow that we can rest assured the Wall will be there for thousands of years to come, Emmanuel says: “The odd brick may fall, but the wall isn’t going anywhere anytime soon. We will have more pressing concerns.”
2,000 years later
Indeed, the Herodian lower part of the Western Wall has stood for around 2,000 years. Tradition holds that the wall was part of the monumental Second Temple complex built by Herod the Great, the vassal king of Rome who ruled Palestine from 37 B.C.E. to 4 B.C.E.
Modern archaeology holds that Herod may have begun the complex but didn’t finish it. Construction would have taken decades and the Wall was only completed at least 20 years after Herod’s death, which is believed to have happened quite horribly in 4 B.C.E.
Herod, and whoever after him, built the Western Wall using two sorts of limestone, harder and softer. The quarries supplying the stone for this massive endeavor – such as the Ramat Shlomo quarry – produced both types, Emmanuel explains.
The Herodian layers in the wall have both, which is why, 2,000 years later, the wall looks a tad patchy. The resistant stones have been eroding at a rate of 1 to 2 millimeters every 1,000 years. The softer type are deteriorating at 10 times that rate, losing 1 centimeter every 1,000 years.
But the catastrophic failure of the stone that broke wasn’t a matter of gentle erosion: the thing suddenly cracked in two and shattered.
It bears adding that the builders of the oldest parts of the wall didn’t use mortar. The stones were meticulously carved to nestle closely, which doesn’t mean there weren’t flaws in their juxtaposition.
Memories of the Second Temple
The Western Wall is the last remaining structure identifiable from the ancient Second Temple complex, which Roman troops leveled in the year 70 after besieging the city of Jerusalem and vanquishing the Jewish rebels who had declared war on Rome five years earlier. (They then built Aelia Capitolina on the site of destroyed Jerusalem.)
The wall is not believed to have been part of the Temple itself. It was part of the structure surrounding the Temple’s vast courtyard on Temple Mount. (In 2016, fragments of colorful tiling from the Second Temple courtyard were found in debris removed from the Temple Mount by the Waqf – the Muslim authority in charge of Temple Mount.)
The instability of certain stones in the Western Wall and other structures on Temple Mount is not a sudden revelation. In 2003, the antiquities authority surveyed the Western Wall, mapping the stones and their physical problems. Another survey conducted in 2009 reported that building materials were becoming detached and that stones in the latest, uppermost, layers were in danger of detaching and falling.
Repair works were done on this Ottoman-era layer by the Israeli authorities, including replacement of mortar, says Zachi Dvira, an archaeologist from Bar-Ilan University who co-directs the Temple Mount sifting project. The works took about three months and were done mainly at night.
But intentions to fix up other parts of the wall, let alone excavate in the area, ran into political sensitivities.
Dvira claims that unsanctioned works by the Waqf, which were not subjected to professional engineering supervision, resulted in changes to the natural flow of rainwater – which led walls on the Mount to bulge. Conservation work by, for instance, Egypt and Jordan did not turn out well, Dvira says. One reason is that they didn’t try to recreate the original look of the wall but used modern stones, he adds.
The Jewish religious authorities – including Rabinovitch, who has been in charge of the Kotel since 1995 – tend to resist conservation works, too, Dvira notes. In their case, he suspects their opposition is more related to the struggle over control of the wall and the nature of worship there.
The brick fragment collapsed smack in the egalitarian prayer zone, where men and women can perform devotions together. Some such as Dvira suspect that the religious authorities in charge of the wall hope the near-accident will persuade the Jerusalem Municipality to pull back from nonsegregated worship.
Some religious figures have even suggested that the giant stone cracked and fell – on the 10th day of Av, the day after the fast commemorating the destruction of the Temples – as a sign of divine umbrage at men and women praying in such close proximity.
Call it gravity
So why did the brick split and shed a large piece some 2,000 years after being lovingly positioned? Catastrophic rock failure can be caused by previous damage, even hundreds of years prior; an inherent weakness in the stone matrix; water seepage, plant roots, later changes to the wall that cause new stresses, and so on.
Mazar points out that the failed brick was in a Herodian layer that sat proud of the layers below it. In other words, the bit that broke off was unsupported, relying only on the integrity of the stone.
But a cursory examination of the fallen piece has Dvira worried. He urges the authorities to keep worshippers a few meters away from potentially raining rocks and, overcoming immaterial opposition, fix the wall.
“I had seen cracks in the stones before, but they looked external,” Dvira explains. But then he saw the stone that broke and split into two. Clearly, the crack in the rock began in the dim reaches of history: There was plenty of dirt inside, and the small part finally holding the rock together finally failed, and gravity prevailed.
Worse: “I went over all the other stones in that area and saw a lot that look in exactly the same condition, with very deep cracks,” Dvira says. “There is no danger that the wall, its Herodian parts, will fail. It is completely stable. But parts of the stone are crumbling and could fall.”
It happened in 2004, for instance: fragments – albeit significantly smaller ones – fell on people in the courtyard, he recounts.
Mazar agrees that if the Western Wall had been properly supervised, or supervised at all, this wouldn’t have happened.
“There is no orderly supervision,” she says. “Somebody needs to keep on top of the state of the stones. This didn’t happen all of a sudden. If there had been supervision, somebody could have noticed the crack earlier. It isn’t anybody’s job at this time, but it should be – to inspect the stones one by one, and see where vegetation needs to be pulled out.”