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in Vietnam a giant secret sleeps It is
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Sondong Cave the world's largest cave
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passage Its size is truly immense almost
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beyond our belief It was hidden for many
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years a true wonder of nature waiting to
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be found Picture a space so very big a
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tall skyscraper could fit inside or a
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whole city street The main cave runs for
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miles It is incredibly high 200 m It is
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also very wide Nature built this giant
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hall over vast stretches of time Inside
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this huge space wonders happen Sandong
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makes its own weather Clouds gather near
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the high ceiling These soft clouds drift
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slowly Mist often fills the air This
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special climate is unique made by the
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cave itself and the moisture within
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Standing in Sandong is amazing You feel
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very very small Ancient rocks around you
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Silence is all around Head lamps cut the
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deep dark It is like another planet a
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place outside of our time a journey into
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earth Sundong's discovery is a tale It
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starts with Mr Ho Khan He was a local
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farmer In 1990 he sought shelter He
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stumbled upon an opening Wind howled
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from within Water roared in the darkness
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He noted its location then left After
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that day Mr Khn could not find it The
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jungle was too dense The landscape was
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very tricky He tried many times but the
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cave entrance was lost For nearly 18
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long years it remained a local legend A
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whisper in the rainforest Then in 2009
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things changed Mr Khn met British cavers
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They were exploring the area He told
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them about the cave He remembered the
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sounds He tried to lead them there After
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many attempts he succeeded They found
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the lost entrance again The British team
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began to explore They were from the BC
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They descended into the darkness What
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they found was breathtaking The passage
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just kept going It was bigger than any
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known cave They measured its vast
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chambers Sandong's true size was
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revealed Inside Sandong nature is an
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artist Giant stelagmites rise from the
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floor Some are over 70 m tall They look
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like strange towers formed by dripping
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water over hundreds of thousands of
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years Each drop adds a tiny layer These
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are sentinels of stone From the high
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ceilings formations hang down These are
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called stelactites They mirror the ones
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below Some are slender and delicate
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Others are thick and massive They grow
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slowly centimeter by centimeter creating
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an alien beautiful landscape all
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sculpted by mineralrich water A key
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feature of Sandong is its dolings These
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are huge collapsed sections of ceiling
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There are two of them They are like
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giant skylights opening the cave to the
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world above They let sunshine stream
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deep inside breaking the endless
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darkness A truly spectacular sight to
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behold These dough lines are incredibly
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important They bring precious sunlight
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into the cave This light allows plants
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to grow deep within the earth's embrace
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They also create microclimates different
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from the rest of the cave These windows
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to the sky are vital for the life that
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below Beneath the first great doine life
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flourishes A lush jungle grows here It
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is named the garden of Edom Trees reach
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towards the distant sunlight Ferns and
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other plants cover the ground This is a
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unique ecosystem hidden deep inside the
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earth A green oasis in the dark A
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powerful river flows through Sandong
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This is the Ralo Tuong River It carved
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out these immense passages Over millions
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of years it worked Its waters are strong
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and fast especially during the flood
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season This river is the cave's creator
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its constant patient sculptor Visiting
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Sundong is a true adventure It is not an
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easy journey Trekers face difficult
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terrain They abs sail into darkness They
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wade through rivers But the rewards are
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incredible To witness this hidden world
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is an experience of a lifetime Sundong
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is more than just a cave It is a natural
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wonder It shows us Earth's hidden power
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and its incredible beauty It reminds us
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there is much to discover Understanding
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Sandong helps us learn about our
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planet's geology and life a precious
