00:00 If you come across a certain well in Portugal, resist the temptation to plunge your gaze into these unfathomable depths.
00:07 This inverted tower, close to the enigmatic palace of the Regaleira in Sintra,
00:12 gives the flesh of a hen to anyone who dares to venture there, while it sinks in a spiral up to 27 meters underground.
00:18 This well was probably not designed to collect water, yet its true purpose remains a well-kept secret.
00:24 Dating from around 1904, it is probably inspired by the mysterious ritual of initiation of the Templars.
00:31 The order of temples had been dissolved nearly six centuries before the construction of this well,
00:35 but their strange practices were revived by subsequent mystical societies.
00:40 Thus, a theory advances that the candidates seeking to be enthroned at the time had to face their most secret fears,
00:46 by facing this well and by unleashing their spiral steps blindfolded.
00:51 When they reached the bottom of the inverted tower, they took off their blindfolds and were faced with this frightening view.
00:58 The only way out of this dark labyrinth was to continue looking up in the air and following the light.
01:05 Imagine walking through the rays of a bookworm, until you come across a book written in an alphabet that you have never seen before.
01:14 You decide to use a translation application, but you get no correspondence.
01:20 Intrigued, you decide to buy the book.
01:23 Then you show it to your friends and family, but no one recognizes this writing.
01:27 The book vendor, Wilfried Voynich, probably experienced the same frustration in 1912
01:33 when he acquired what would later become the most enigmatic book in the world.
01:38 The work is now known as Voynich's Manuscript,
01:41 and it is entirely written in an unknown language that no one has yet managed to decipher.
01:47 The pages of this 15th century codex are filled with botanical sketches,
01:51 but they are not margaritas or lambda roses.
01:55 In fact, they do not look like any known plant, which makes things even more unusual.
02:01 These are seven illustrations of unknown constellations and women swimming in green water.
02:08 By diving deeper into the domain of mysterious parchments,
02:14 we made a trip to the Cumbrian caves in Sisjordani, not far from the Dead Sea.
02:20 In 1952, a team of archaeologists discovered two heavily rusted copper rolls on the site.
02:27 Unrolling these parchments was not an easy task,
02:30 so we decided to cut them into 23 parts to examine them.
02:34 Imagine the surprise of archaeologists to see Hebrew words like "gold" and "silver" appear.
02:40 But no, it was not a millenary bill, but rather a card indicating the hiding place of a treasure estimated at more than a million dollars.
02:48 Alas, this treasure has never been found.
02:51 It is not a fault of having tried, however.
02:53 But you see, the enterprise is not as easy as it seems.
02:56 Some terms of the copper roll are extremely technical,
02:59 and the mentioned geographical locations remain mysterious.
03:03 There is one last possibility.
03:05 Maybe all this is just a work of fiction, like an old-time pirate story.
03:11 People often talk about the almost obsessive gaze of the joconde,
03:17 who seems to follow you wherever you go.
03:20 But here is a small question.
03:22 Does it only have eyebrows?
03:23 You saw if you answered "no".
03:26 And this total absence of eyebrows only adds to the mystery of his gaze.
03:31 The most common explanation is that the criteria for beauty of the time were different,
03:35 and maybe the hair on top of the eyes was a common practice at the beginning of the 16th century.
03:41 But if you look at other Italian paintings of this period,
03:44 like "La Sciavona" or "The Portrait of a Young Unknown",
03:48 well, here are eyebrows.
03:50 So, not everyone was entirely satisfied with this theory,
03:54 like the French engineer Pascal Cotte.
03:56 He spent 3,000 hours scanning the painting to see through each layer of Leonardo da Vinci's masterpiece.
04:03 He claims that Mona Lisa once had eyebrows,
04:06 but that they disappeared over the years of cleaning and restoration.
04:11 However, some historians still question these conclusions,
04:15 which means that the style of Mona Lisa remains a mystery to this day.
04:20 You decide to go to Rio de Janeiro,
04:25 and everyone tells you how much the world of sugarcane is essential.
04:30 When you see the mountain from afar,
04:33 you realize that the stone has a cavity.
04:35 But around noon, it changes its appearance.
04:38 The shadow of the cavity then takes the shape of a bird,
04:40 that of an ibis to be precise.
04:43 This appearance is reminiscent of the Egyptian god Thoth.
04:48 As if the ancient pharaohs had visited Rio at the time
04:51 and had been inspired by this natural phenomenon.
04:55 But it is probably just a simple coincidence among so many others.
04:59 The real mystery, however, lies in the waters around the sugarcane.
05:04 In the 1980s, archaeologist Robert Marx learned from the Brazilians
05:08 about the existence of a hidden treasure in the bay of Guanabara.
05:11 He dived and discovered a number of Roman amphorae.
05:15 You know, those old jars that you find everywhere in Italy.
05:19 His discovery could potentially provide proof of a Roman shipwreck
05:23 that would have reached Brazil nearly 17 centuries
05:26 before the Portuguese set foot there.
05:29 He never managed to pursue his research.
05:32 And to this day, the idea of a Roman presence on the Brazilian coast remains uncertain.
05:38 The real location of Cleopatra's tomb is not the only mystery of ancient Egypt.
05:45 Many secrets are engraved in the walls of these ancient structures,
05:49 as in the funeral temple of Seti I.
05:52 Look closely at this hieroglyph,
05:54 and you will notice that it looks like a modern helicopter.
05:57 Take a look on the right, and you will see an engraving that looks like a submarine.
06:02 Disconcerting, isn't it?
06:03 The most plausible explanation lies in the successive marks left by the different pharaohs.
06:09 When a new monarch came to power,
06:11 he added his own hieroglyphs above those of origin.
06:15 But this is still a subject for debate.
06:17 Because some Egyptologists believe that these mysterious hieroglyphs
06:22 could represent a kind of ancient technology.
06:26 The same applies to Dandera's light bulb.
06:29 This engraving, discovered in an underground passageway of the temple of Hathor,
06:32 is subject to controversy.
06:35 Some researchers suggest that it would simply represent the rising sun,
06:40 while others interpret it as proof of the existence of a kind of modern lighting system.
06:45 And it does look like a Krux tube,
06:48 one of the first experiments in the field of electrical discharges.
06:53 Although there is no concrete proof that the ancient Egyptians had or had modern electricity,
06:59 some believe that this theory could help explain why many tombs discovered until then
07:04 did not present any residue due to the use of oil lamps or candles.
07:09 We have talked a lot about the mysterious pyramids of Egypt.
07:15 But people tend to forget that other enigmatic structures existed long before them.
07:21 Our next stop takes us to Turkey.
07:24 The summit of a hill known as Göbekli Tepe,
07:28 near the city of Urfa, holds an ancient secret.
07:31 It features about twenty encinitas of circular stone,
07:34 over 11,000 years old.
07:36 Many of these are adjoined to heavy stone columns,
07:40 carved in the shape of a T, and adorned with strange human figures at their hands.
07:45 The most widespread theory is that it is the oldest temple in the world,
07:49 probably used for rituals or festivities.
07:52 But its greatest mystery lies in the way it was built.
07:55 Because this site existed before the domestication of animals or the invention of metal tools.
08:01 Thus, its construction must have been particularly difficult,
08:04 and raises the question of our understanding of history.
08:07 I hope you are not dizzy,
08:12 because we are about to fly over the lines of Nazca.
08:15 You have probably already heard of these huge and mysterious motifs,
08:19 engraved in an arid region of Peru.
08:22 They are in many different shapes,
08:24 like a spider, a monkey,
08:26 and even a kind of alien with globular eyes,
08:29 which is probably just a simple fisherman.
08:31 Anyway, this story experienced some twists in 2022,
08:36 when no less than 168 new drawings were discovered.
08:39 The first could only be seen from the air.
08:42 But these new motifs are much smaller,
08:45 and can be observed on the ground.
08:47 However, one thing they have in common is that their function remains totally obscure.
08:53 Some consider them to be the world's largest calendar.
08:57 Others suggest that they may have been used as tools for agricultural purposes.
09:01 Of course, many other theories have emerged in order to give meaning to the Nazca lines.
09:06 But the truth is that it remains one of the greatest unsolved mysteries in history.
09:10 (upbeat music)
Comments