4.6 billion years since its creation, the earth has continued to surprise us with its natural wonders. today we will take a look at a volcano that sits on the great plains of east africa. on this scorching continent, we can directly feel the earth's 30 million-year-old pull. a lake of lava, one of the oldest in the world, reveals itself to us. ♪ we approach the molten lava. it is as if we can feel the

breathing pulse of the earth. ♪ as the colorful volcano is created, and how you is this possible? great nature, the scorching land of africa, we take a closer look at one of the earth's unique volcanoes. we journey into africa, to a land situated about 13 degrees north of the equator. the danakil lowlands, found in

ethiopia, africa. they form a depression that is over 100 meters below sea level. here extends a concentration of active and sometimes violent volcanoes that are unmatched in majesty. we find ourselves below sea level in what has been called the cruelest place on earth. the haze of stifling heat looks hot indeed. but that is not surprising. for in summer, temperatures exceed 50 degrees celsius, making it the hottest place on earth.

the danakil lowlands are close to the size of the gulf state of qatar. as we proceed, the ground begins to turn a whitish color. this is, in fact, salt. since the area lies well below sea level, it was repeatedly flooded over time, and after each flooding followed a period of evaporation, creating huge deposits of salt. suddenly, we see a long line of camels. as we follow, we find a crowd of men working under the blazing sun. the sweat is running down their backs. and they appear to be digging for something. they are men of the afar tribes

who make their living from the salt they extract from the danakil salt flats. the salt that is pulled out here is transported all across ethiopia. the salt forms a layer over a kilometer thick, deep under the ground. even now the danakil lowlands blesses us humans with a valuable gift. in the northern part of the danakil desert tow airs volcano with a scorching lava lake. this is erta ale. fierce volcanic activity has been going on here for over 100 years, attracting the attention

of scholars from around the world. ♪ as we approach the mountain, the lava covering the ground makes our progress a lot rougher. erta ale has tremendous power, spewing out lava over a great distance. we arrive at the village that will serve as the base camp. it is a four-hour walk from here to the summit where the lava lake is located.

it is now three hours since we started walking. only a little further until we reach the crater. the lava rock beneath our feet is clearly starting to change. there are distinctive shapes which resemble crashing waves. actually, only three months earlier a major eruption occurred and a large amount of molten lava covered this area.

we finally reach the volcanic crater of erta ale which holds immense power. inside the cavity, seen on the center of the screen, is the lava lake. ♪ look at that. this is the full view of the lava lake. the diameter is approximately 15 meters.

only 7 meters below our feet boiling lava has built up to the rim. such lava lakes are extremely rare, with only five known to exist in the world. as we approach the lava lake, we hear an alarming sound.

the temperature of the lava is about 1,000 degrees. when you stand right at the edge of the crater, a burning heat wave hits us. at night, the erta ale lava lake reveals its formidable strength.

>> the sound, the smell, the heat, everything has a completely different intensity from what it was like during the day. the lava lake is experiencing a series of minor eruptions.

molten lava comes bubbling up from the deep underground magma chamber. look there. wide cracks have appeared on the surface of the lake.

although the lava that bubbled up is cooled by the air at the surface of the lake, and solidifies, new lava continuously bubbles up from underground and therefore new cracks are created.

after a while, the surface of the lava lake begins to swell up. it rises to a height of about 50 centimeters, proof that the pressure of the lava that boils up from underground is extremely high.

this cycle repeats itself about once every 20 minutes. it is as if the earth itself is breathing. ♪

♪ the danakil lowlands, ethiopia, the land below the sea. there are up to 30 volcanoes concentrated in this area. why is it that so many volcanoes were formed right here?

the clue to solving this mystery lies near erta ale. this is a volcano called dallol. the very flat shape of the crater makes it extremely unique. vivid colors can be seen within the crater. minerals from below the surface, such as sulfur, iron and salt, spring up along with hot geyser water create this mysterious spectacle.

the many volcanoes in the danakil lowlands are deeply related to the tectonic rifting that has been going on for 30 million years. 30 million years ago, the african continent and the arabian peninsula were connected. later, a part of the arabian peninsula moved significantly east, as a result of continental rifting. the two areas of land sank below the sea. however, further crustal deformation isolated the area from what is now the red sea and

caused the sea water within to evaporate, thus the danakil lowlands were born. an entire section of the earth's surface was stripped away here, and so the underground magma is closer to the surface than normal, right below the ground. as a result, hot water and lava containing various minerals frequently burst out of the ground. this large scale rifting has been taking place for 30 million years.

the border line where the ground was torn apart now remains as a 1200 kilometer long cliff in the western part of ethiopia. the cliffs are home to many rare animals. this is the gelada, a monkey indigenous to ethiopia. many of the gelada monkeys originally lived in the grasslands, but started living above the cliff in order to protect themselves from predators. a decision is made to approach these magnificent cliffs of ethiopia.

a local geologist joins the group to take a closer look at the cliffs. >> the sandstone, so they are hard rocks, resistant, but during -- before 60 to 50 there was erosion and that erosion has removed the softer material and what we see there is the cliffs,

which are resistant to weather and erosion. >> if we look carefully, we see a number of cracks running vertically down the cliff. >> the water goes through weak zones. you have the rocks and you have the cracks opening. you see them. you see the weather percolates when it rains, it percolates through the fracture. then finally it will -- it will spread and then it forms. so in the future it will be moved and then we will have one here, one cliff here, and another one there, maybe after hundreds of thousands of years or so, or a million years.

>> the scars left by continental rifting, these giant cliffs will eventually collapse and disappear. they hike up to take a closer look. >> this is sandstone which has fallen from the top. how can a boulder this large crumble off? it seems like the cliff is already beginning to collapse, little by little. we have come just below the crack that we saw from a

distance earlier. >> the cracks of the rocks. this one drift. then this one, another crack. >> the giant cliffs are scars left by giant shifts in the earth's crust, spreading across ethiopia. in fact, these cliffs are also deeply connected with the lives of the local people.

surprisingly, many local people are said to climb the cliffs at least once a week. the reason for this is soon to be revealed. >> okay. >> and here. >> okay. >> here. >> right hand. >> here, okay. >> since the cliff is made of sandstone, climbing is slippery and treacherous. 30 minutes into the ascent, the

scenery has begun to change. >> after climbing for an hour, there is a clear view of the surroundings. this place is over 60 meters high.

and it is very near to where the locals head for. however, the greatest challenge lies ahead. the path is only 50 centimeters wide, just enough for a person to pass through. that is quite a drop.

and now it's clear why the locals regularly climb the cliff. it is a church. >> in the past, jews and muslims persecuted the christians of ethiopia. ♪

>> so the christians made these intimidating and forbidding cliffs their sanctuary. ♪ 30 million years of the earth's pulse resonates here, in ethiopia, on the scorching continent. the earth's hot breath is still felt here. ♪