“The most beautiful experience we can have is the mysterious …the fundamental emotions which stands at the cradle of true art and true science.” So said by Albert Einstein. Arguably true, but how are we going to experience something mysterious for our simple and lowly selves? Thinking of our very own existence and beholding and scanning across the boundless skies inlayed with countless glorious stars are mysteries we all perhaps have pondered upon. Other many things that offer us something to profoundly ponder for life are the mysterious places and/or structures built in prehistoric times. Famous of which are well-considered below.
Easter Island

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Easter Island is part of Chile but is situated 3,600 km (2,237 mi) from mainland South America, becoming one of the most isolated inhabited islands in the world. It was discovered by European explorers more than 300 years ago in its extremely isolated geographical location-Southern Pacific Ocean.
The discovery of a vanished civilization has evoked much controversy among archeologists, the curios people and even among common folks. Those archeological human statues, called moai (shown above) are indicative of a relatively advance and complex culture that ever developed in the Neolithic society. Today part of the island, named Rap Nui National Park is preserved as one of the world's heritage parks.
Archeologist argued that their stone-working skills and method of writing were comparatively far superior to any other Polynesian culture. For more than one thousand years, this highly developed society flourished before its eventual collapse. Why this ancient, yet remarkable civilization did went away? What drove its population to extinction? These are the concomitant questions that consequently surfaced shortly after this baffling archaeological discovery. A host of intellectuals would later offer their own line of reasoning, while the theory put forward by the American evolutionary biologist Jared Diamond has been receiving much wider audience. Diamond's thesis can be summarized as follows: a gruesome social chaos happened in the island after a few centuries of settlement. The inhabitants went into destroying their forests, degraded the quality of agriculture of their land, exterminated their plants and caused their animals to extinction. They eventually lodged wars against each other and practiced cannibalism that eventually led to the extinction of their race. Thus, the desolation of the island when the Europeans first set foot on this tiny piece of land hundreds of years after the disappearance of the once prosperous and flourishing civilization.
Diamond's account appears conclusive, but no one can be so certain enough. It's consensus that intellectual pursuits of this nature often breed no certain conclusions. They sometimes remain purely speculative and the mystery behind the disappearance of the once vibrant civilization at Easter Island remains in the forefront of our thoughts and imaginations.
The Ruins of the Maya

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The Maya civilization was one of the remarkable civilizations of the ancient times whose extent of influence reached as far as the now independent nations of Central America, namely: Mexico, Guatemala, El Salvador, Belize and Honduras.
Testaments to the Mayan's once flourishing culture and civilization are the still imposing remnants of the once mighty and grand architecture of this ancient people. Some of which is the Palenque (image shown above), a Mayan archaeological site located around 130 km south of Ciudad del Carmen, Mexico. A UNESCO world heritage site, it is now preserved by the government of Mexico, calling it the Pre-Hispanic City and National Park of Palenque.
For reasons still unknown, the Mayans suddenly started to decline around 900 A.D., and neither the Classic period nor the advent of the Spanish and their subsequent occupation of most of South America were responsible. Archaeologists have long proposed diverse theories for their collapse. Non-ecological and ecological reasons are the two opposing theories. Ecological hypotheses include environmental disaster, epidemic disease, and climate change. There is evidence that the Maya population exceeded carrying capacity of the environment including exhaustion of agricultural potential and over hunting of megafauna. Some scholars have recently theorized that an intense 200 year drought led to the collapse of Maya civilization. The drought theory originated from research performed by physical scientists studying lake beds, ancient pollen, and other data, not from the archaeological community (Wikipedia).
Newgrange Megalithic Passage Tomb

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Dating back as far as 5000 years ago, the Newgrange Megalithic Passage Tomb in Ireland is one of the oldest structures in the world, hundreds of years predating the mighty Stonehenge in England and the Great Pyramids of Egypt. Lying hidden for more than 4000 years, it was discovered initially by men looking for building stones in 1698. Its restoration only begun in 1962 and saw it finished in 1975 under the supervision of the Irish archaeologist, Professor Michael J. O'Kelly. Experts have figured out that the construction of this magnificent edifice took the builders more than seventy (70) years to complete.