The San Francisco Art Institute is one of the oldest art schools in the country, and thousands of students pass through its corridors every year, admiring the massive murals on the walls from world-renowned artists. It houses some of the best pieces of contemporary art ever created.

But when Facilities Manager Heather Hickman Holland was walking the school’s halls one afternoon, she noticed something odd on one of the white walls. Confused, she peered closer, suddenly realized what she was looking at, and gasped.

Thousands of students and visitors walk the halls of the San Francisco Art Institute every year. The walls are adorned with massive murals from world-famous artists who hail from all over the world.

At 140 years old, the institute is one of the oldest in the United States and the oldest west of the Mississippi River. And, as one worker discovered, not everything about the school is what it seems.


Facilities Manager Heather Hickman Holland is an employee at the institute and has years of experience dealing with the school’s inner workings. However, one afternoon while roaming the halls, she noticed something that seemed off.

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As she was looking up at the white walls, she saw some markings she initially thought were clusters of cobwebs. But, as she peered closer, her eyes widened and she gasped.

The “cobwebs” she thought she was looking at weren’t that at all. They were actually the faint outlines of something underneath the white paint covering the walls of the Institute. So, she headed to the school’s library to investigate.

She combed through documents that detailed the history the school. She never really had a reason to take a super in-depth dive into the school’s past, but what she found astonished her.

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She learned there were a series of murals painted on the original school’s walls during the New Age era, which was the period of time after the Great Depression when major reforms were made.

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It was during that same exact time period a collection of murals called the Works Progress Administration murals were created. They were part of the post-Great Depression Federal Art Project.

The painting appeared to be a “fresco” painting, which meant it came from an ancient technique of brushing watercolors onto wet plaster. The discovery attracted the attention of a woman named Molly Lambert.

Lambert was an architectural conservator, so naturally she jumped at the chance to take a crack at carefully uncovering the historic find and preserving as much of its integrity as possible.

Lambert and her colleagues knew they had to be incredibly gentle taking the paint off the walls. There were many layers to remove, and ensuring the fresco’s safety was the most important mission.

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It was far from cheap to hire a team to take apart such a large section of wall, but luckily, the school managed to secure large grants from the Henry Mayo Newhall Foundation and Save America’s Treasures.

The massive undertaking was finally in full swing. The first several layers of paint were brushed away with ease, but once they got to the actual watercolor, they gently scraped little by little to avoid destruction.


One of the men featured in the painting had a cigarette dangling out of his mouth. Lambert joked about the character, saying, “Look at this guy, he even has a cigarette that says Chesterfield on it. He’d be vaping today.” 


The painting reminded the team of a massive mural hanging the art school’s auditorium painted by a prominent Mexican artist named Diego Rivera in 1931. The team wondered if their new find was just as old.

Slowly but surely, the team was able to take off all of the crusted white paint, leaving an absolutely breathtaking picture behind. This was the kind of discovery of which any architectural conservator’s dreams were made.


Lambert said of the final product, “Of course when you uncover something like this you’re not sure what the quality’s going to be. But this is fantastic.” But, who was artist behind this 1930s masterpiece?

Lambert and Holland learned the artist behind the fresco was Frederick Olmsted, a man considered the father of American landscape architecture. The women made another discovery after they ventured to the area supposedly depicted in the painting.

A local restaurant called Brick & Beam was built inside the exact same building that once served as the marble factory in Olmsted’s piece. The fresco was full of more intricacies than anyone imagined.

Now that Olmsted’s piece was found, the school plans to uncover more of the hidden murals and turn the white hallways into dazzling spectacles. They knew that some of the greatest artistic discoveries were covered by time.

Museum curators and art historians are knowledgeable gatekeepers when it comes to the body of work left behind by the most famous artists in the world. The important work they do in collaboration with scientists has led to many new discoveries.

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They don’t just admire art — they work on it. Whether it’s restoration or maintenance, they are hands on and attempt to understand the way that beloved masterpieces were created. Every now and then, they find something incredible.

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Studying Leonardo da Vinci leads to man breakthroughs for historians. He had a mind for so many things. A genius in the truest sense of the word, he dedicated his life to scientific and architectural pursuits in addition to his art.

Da Vinci was secretive and strange, often unable to complete artistic projects because of his wandering mind and relentless pursuit of knowledge. This makes the important discovery even more apt. Of anyone, it would be da Vinci who left behind a secret message.

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Born in April of 1452, he was the illegitimate son of a fifth-generation notary. This may seem unlucky but is actually part of the reason he became the artist and inventor he did. Had he been born a legitimate son, life would’ve been different.

At the time, children would follow in their parents footsteps. So, he would’ve gone to school to be notary and possibly would have never explored his other talents. His status allowed him to freely explore his passions and a non-traditional education.

He was largely self-taught and wasn’t afraid to push boundaries. For example, he often dissected the corpses of humans and animals. This dedication to understanding anatomy helped him create the most realistic and vivid human forms in his art.


In his twenties, da Vinci was almost executed due to sodomy charges, but was spared. He then disappeared for two years before reemerging to complete an artistic commission for a chapel in Florence.

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He often wrote in reverse in his journals (one of which would later be sold to Bill Gates for $30 million) that are full of scientific and philosophical revelations. Now, a new discovery is reigniting interest in the mysterious genius.

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The Virgin on the Rocks may not have the same recognition of The Last Supper or The Mona Lisa, but it’s got an interesting past and is known to be a hiding place for yet another work by da Vinci that was kept secret for so long.

The painting in question is actually one of two. The first one hangs in the Louvre in Paris and the second in the National Gallery in London. Da Vinci painted the one in the Louvre first and recreated it due to popular demand.

Despite it technically being a copy of the first, the National Gallery version is special for a few reasons. One being that Da Vinci painted it with his fingers instead of a paintbrush. The other thing that set it apart shocked researchers.

Using infrared and hyperspectral imaging on the painting revealed a secret image behind the paint that had dried over five hundred years before. It turns out, there was a completely alternative version of the famous painting.

Because the hidden drawing was made with a zinc material, the special imaging techniques got a clear picture of the heretofore unseen sketch. Mary and the infant Jesus are shown in totally different positions than the final painting displays.

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In a press release from the National Gallery, a spokesperson explained the differences saying, “In the abandoned composition both figures are positioned higher up, while the angel, facing out, is looking down on the Infant Christ.”

The National Gallery

This revelation is the the artistic equivalent to hearing a new Mozart composition. Something new had been hiding in plain sight after all these years. New is a big deal, especially for a small collection like da Vinci’s.

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The artist’s body of work is compromised of fewer than twenty pieces of art. So, this discovery is even more significant. Academically the sketch is invaluable. The insight into the planning and sketching process offers new information about the artist’s vision.

As someone who already struggled with completing paintings, fate intervened cruelly toward the end of his life when his right hand became paralyzed. Even so, he continued to create art to the best of his ability before his death. Some even came along postmortem.

See, today, historians most often associate Da Vinci with present-day Italy, where he was born and spent most of his professional life. However, he may have completed his boldest creations in Amboise, France. Da Vinci did way more than just paint.

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Notwithstanding his innovative artwork, Da Vinci’s mechanical prototypes were centuries ahead of their time. About 500 years before the invention of the airplane, he concocted a design for a flying machine.

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Sketches from the inventor’s final years revealed a design for a mechanical lion. Da Vinci reportedly built a couple versions of the lion for King Francis I of France. The protoypes took his court by storm.

Today, Da Vinci’s residence at Château Clos Lucé is a museum. Its president, François Saint-Bris, has a longstanding fascination with the lion automatons. All without electricity, the contraptions could walk and move their heads and tails!

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In 2009, François proposed a daring idea to celebrate Da Vinci’s legacy: Would it be possible, he wondered, to fully recreate a lion automaton based on the polymath’s original blueprints?

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For most historians and art critics, this was one Da Vinci code that even Robert Langdon couldn’t solve. Luckily, the staff at Clos Lucé tracked down a brilliant craftsman, whose sharp intellect might even rival Da Vinci’s.

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The museum staff got in contact with a French artist named Renato Boaretto. A veteran designer, he made a name for himself by using old-fashioned technology to build truly stunning machines.

Renato’s specialty came in the form of lifelike mechanical figures. No piece quite the same, his work extended from a magician who makes a woman levitate to a musician capable of moving his bow across a cello.

Renato Boaretto

When he heard the museum’s proposal about the lion reproduction, Renato naturally couldn’t resist. However, he had very little to work on. Only fragments of the original blueprint were available, so Renato would have to fill in the blanks.

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And while Renato had sculpted just about every kind of face and body under the sun, so making a lifelike lion wasn’t too daunting, he harbored some concerns about the practical design of the machine.

Claudio Boaretto

Even the known aspects of the lion’s design weren’t exactly encouraging. Based on the dimensions of the real-life beast, it would come out to about 130 pounds. At the same time, it had to leave enough space to not crush the delicate gears and pulleys.


Complicating matters further, Da Vinci’s sketch for the motor inside the lion was lost forever. To make it actually walk, Renato would have to borrow from his past inventions as well as from Da Vinci’s other machines, which include a knight automaton.

Over the course of many months, Renato assembled his lion, bringing together the toughest parts of both art and engineering. The artist had to make sure the animal’s mane and face looked realistic, and all the machinery inside it actually had to work.

As large as the automaton was, Da Vinci designed it to be powered by the crank of a simple key. Renato laid out his model the same way. On the fateful day of the demonstration, he stuck the key inside and prayed that all his labor wasn’t in vain.

Miraculously, the lion walked! Though it could only take about ten steps at a time, it didn’t need any kind of track or additional power. Using Da Vinci’s notes, Renato snuck in one final surprise as well.


Once the lion finished its walk, a compartment in its side popped open. Then, it revealed a bouquet of lilies, the national flower of France! The museum figured Da Vinci included this as a tribute to his patrons in the French monarchy.

Visitors at the Clos Lucé applauded Renato’s accomplishment. Even in the age of the smart phone, this-16th century technology boggled people’s minds. It may also be a big step toward future discoveries.

After all, Da Vinci produced countless other designs that almost defy imagination. And even in his most famous masterpieces, experts are uncovering hidden meanings and patterns.

The Mona Lisa is one of the most famous pieces of art ever created. There is so much mystery surrounding Mona Lisa that historians continue to study the painting today, and after all these years she still has secrets to reveal…

In 2015, a French scientist using reflective light technology discovered a portrait of another woman hiding beneath the painting we see now. The underlying portrait is believed to be Da Vinci’s first draft of the famous painting, though it’s difficult to confirm. And Da Vinci isn’t the only artist with a secret.

Jan van Eyck, the Netherlandish painter, created the famous Arnolfini Portrait in 1434. The painting depicts Giovanni di Nicolao Arnolfini, an Italian merchant, and his wife, Constanza Trenta. While the renowned work is impressive in itself, there’s more to the painting than meets the eye…

Take a closer look, you’ll see a mirror centered in the background of the painting. Reflected in the mirror are two other figures who appear to be looking at the Arnolfini’s. Based on our logic of mirrors, one of the figures is presumed to be the artist, Van Eyck, subtly eternalizing himself in the portrait.

We can’t talk about art without bringing up the chiseled bod of David. Arguably one of the greatest sculptures of all time, Michelangelo’s statue of David stands 17 feet tall. Seriously, we have to admit, David doesn’t really have a bad angle going for him. But looking up at David does distort one thing that might change the way you consider the work.

His body is anatomical perfection, and, paired with his confident stance, David is often thought to be sculpted as “hero.” Looking at David at eye level, however, reveals a different story. His expression shows concern and fear, which makes sense given he is about to engage in a battle with Goliath!

This one is a touch macabre. In 1533, Hans Holbein the Younger painted The Ambassadors. The work showcases two rich ambassadors, seemingly healthy and in their prime, surrounded with their fine material goods. While the portrait is strikingly rich in color, the hues defy the underlying message of the work, which is far from vivifying.

Looming at the feet of the ambassadors is an anamorphic perspective of a skull. This piece was intended to hang in a stairwell so, at the angle of ascension, the skull would jump right out at you. The skull was to serve as a memento mori, which translates to, “remember you will die.” So much for a welcome mat, huh?

Despite his name, Pieter Bruegel the Elder is not a wizard. Unfortunately. What he is though, is one of the most notable artists of the Dutch and Flemish Renaissance painting. In 1559, he created the Netherlandish Proverbs. It may look more like a Neanderthal-ish bedlam, but this raucous scene is actually telling a story — 112 stories to be exact!

The painting literally illustrates 112 different proverbs and sayings from the Netherlands. Some of which include, “To be a pillar biter” and “Armed to the teeth.” But the real proverb here is, if you’re not Dutch, you’re not getting much (at least not much face time in a Bruegel painting)!

The Sistine Chapel. You may have heard of it… Well, way back in 1512, Michelangelo was commissioned by Pope Julius II to paint the story of Genesis across 9 sections of the concave ceiling. Michelangelo’s work would come to be recognized as a cornerstone of high renaissance art. Some speculate that beyond a masterpiece, the artist also left behind a message…

Michelangelo spent years studying human anatomy. With that deep understanding, he was able to depict people with greater realism and insert more cerebral meaning into his work. In this famous section, God is surrounded by what looks like a brain. This insinuates that not only did God give Adam life, but also the ability to reason and think.

The Last Supper by Leonardo Da Vinci is almost as famous for its rumors of secret meanings as it is for its artistic brilliance. Da Vinci was unique in his genius, and much of that is to due to his vast and diverse passions. Aside from an artist, Da Vinci also identified as a mathematician, scientist, inventor, and even a musician.

And when a fellow musician admired Da Vinci’s work, he noticed something peculiar. When the five lines of a musical staff are drawn across the supper, the bread rolls combined with the apostle’s hands create musical notes. When you follow Da Vinci’s signature style of right to left, the notes make up a 40-second musical composition.

Vincent Van Gogh created Café Terrace at Night in 1888, a scene so charming, you can almost hear accordions. Some art historians have a different take on this painting though. There are theories that posit this café might have a more symbolic impetus, coming from the son of a Protestant minister…

There have been many comparisons with Van Gogh’s Café Terrace and Da Vinci’s Last Supper. The central figure in white is thought to be a representation of Jesus, while the dark figure in the doorway is speculated to represent Judas.

There is a good story here, but first let’s take a moment to appreciate the name of this painting’s creator, Hieronymus Bosch. Ohhh, it’s so good! Hieronymus Bosch is the creator behind this triptych oil painting titled, The Garden of Earthly Delights. What is even more delightful are the secret, behind-the-scenes notes…

These notes, found on the bottom of a tortured soul in the “hell panel” of the painting, translate into approximately 28 seconds of what can only be described as a reject Nokia ringtone. This melody is widely referred to as “the butt-song from hell.”

The legendary Mexican painter Frida Kahlo had a husband who was, apparently, a painter as well. Just kidding, Diego Rivera is totally a big shot. Due to his notoriety, in the early 1940s, Nelson Rockefeller commissioned Rivera to paint a mural, Man at the Crossroads for the Rockefeller Center in New York City. Alas, even the richest of the rich don’t always get exactly what they want…

Rockefeller didn’t appreciate the inclusion of the communist revolutionary Vladimir Lenin in the mural, so he had the painting destroyed. In response, Rivera re-created the mural in Mexico City. Not only was Lenin even more prominently featured, but Rivera, not so coyly, painted in Rockefeller’s father below the bacterial illustration of syphilis.