CNN News:60年前消失的岩心被归还 或有助于揭开巨石阵起源之谜

Which of these landmarks is the oldest — Stonehenge, The Colosseum, King Tut's Tomb, or Chichen Itza? To visit the oldest monument on this list you'd have to travel to Salisbury Plain, England where you'd find Stonehenge.
Archeologists believe it was built in stages starting around 3,000 B.C, but part of Stonehenge has been missing since 1958 and it wasn't until this week that its return was announced. Stonehenge was constructed with giant sarsen stones, sandstone blocks that are common in southern England. In the 1950s, cracks were found in one of the sarsens, so its core was drilled out and metal rods were put in it to keep it standing. But what happened to that core? An employee from the company that helped repair the sarsen held onto it. He put it on the wall of his office, and the man eventually moved to America bringing the three and a half foot core with him.

The night before he turned 90 years old, he decided to return it to England. And the company that maintains the monument says it hopes the core will help them understand more about the prehistoric structure. One thing archeologists and geologists don't know exactly is where Stonehenge's stones were mined. There are at least two other cores that were drilled out of Stonehenge in the 1950s, but where those are, like the monument itself, remains a mystery.