Scientists have unearthed a town in eastern Bulgaria they say is the oldest town found in Europe to date. The researchers say they found 6.5 feet thick stone walls dating back to 4,700 to 4,200 B.C. Salt bricks were found in the town and scientists say the residents may have boiled water from nearby salt springs to bake into bricks.
Nina Sen is a frequent contributor to Live Science’s Life’s Little Mysteries series: an exploration and explanation of our world’s phenomena, both natural and man-made. She also writes astronomy photo stories for Live Science's sister site Space.com.