Difficulty: Summiteer (Level 3)
A long time ago, when the Romans wanted to build a new temple, they would go to the nearby quarries in Tivoli. They would chisel out blocks of soft rock called lapis tiburtinus, which is now known as travertine. Then, they would float the blocks downstream on rafts to the workers in town.
Today, the same quarries that built Rome with their distinctive pock-marked travertine are still being dug out to build a new generation of churches, temples and mosques around the world. They are also used for constructing banks, museums, government buildings and private homes.
While other countries have versions of the sedimentary limestone, Roman travertine is unique because it is quarried underground in the sulfuric springs and basins around Tivoli.
Made up mostly of calcium carbonate minerals, Roman travertine was formed hundreds of thousands of years ago by deposits of calcium, sulfur and other minerals.
