A couple celebrates summer solstice at a stone carved solstice marker at the Kokino megalithic observatory, on June 20, 2012. The 3,800-year-old observatory was discovered in 2001 in the northwestern town of Kumanovo, 70 km (43 miles) north of Skopje, and is ranked the fourth oldest observatory in the world, according to NASA. (Photo by Ognen Teofilovski/Reuters)
