Dating back to around 3600 BCE, the Knap of Howar is the oldest building in the world and is most likely the oldest house still standing. The Knap of Howar consists of two stone-built houses that were discovered in the 1930s when erosion revealed parts of the stone walls.
The zircon crystals from Australia's Jack Hills are believed to be the oldest thing ever discovered on Earth. Researchers have dated the crystals to about 4.375 billion years ago, just 165 million years after the Earth formed. The zircons provide insight into what the early conditions on Earth were like.
Lying some 150km west of London in the Wiltshire countryside, Stonehenge is perhaps the world's most awe-inspiring ancient stone circle. Older than the Great Pyramids and the Roman Empire, the origin of its story began some 9,000 years ago.