Go back in history to ancient civilizations by learning about the rocks on which they were built. Hot Rocks shows how geology has played a key role in Mediterranean life — from the way people look, to what they believe, to the buildings they live in, to what they eat. The geological features of the region have shaped the development of art, money, concrete, roads — even religion.

With modern analogies that draw on everything from a cup of Turkish coffee to a can of beer, geologist Iain Stewart uses everyday life to draw parallels with the ancient past, demonstrating how geological influences permeate culture and history.

Risky Rocks
Iain travels from Turkey to the Greek island of Santorini, explaining that the Mediterranean is one of the most geologically dangerous places on Earth.

During this tour, he answers some of the region's most baffling historical questions: What forces brought one of the world's greatest empires to its knees? How did the inhabitants of a Greek island escape a devastating volcanic eruption? And what can really explain the biblical story of the massive destruction of the cities of Sodom and Gomorrah?

Architecture
Iain explains why the Egyptians built with triangles, the Greeks with rectangles and the Romans with circles. The answer, as always, is in the rocks. Starting out at the pyramids of Giza, Iain explains why the Egyptians used limestone rocks for building the pyramids and how sandstone influenced the building of the temples at Luxor.

The Greeks built with marble, which is stronger than sedimentary rocks like limestone, allowing for larger spans and more slender supports. Geology dealt ancient Rome the best hand of all — lots of volcanic ash, which when mixed with lime and lumps of rubble formed a concrete that set quickly and was waterproof.

Art
Iain begins in France at the caves of Lascaux, where some of the earliest examples of human art are found. Ten thousand years after the cave paintings, the ancient Egyptians unearthed more color — adding yellows, oranges, greens and blues to their repertoire.

Iain also travels to Spain's Alhambra palace, where Arab alchemists developed new colors in their quest for gold. Modern colors were developed with the help of the periodic table of elements, allowing art to become even brighter.

Belief
Iain looks at how the rocks beneath our feet have shaped our beliefs about how the world works, beginning in ancient Greece. He moves on to Italy, where the course of Christianity in Europe was heavily bolstered by the Roman emperor Constantine.

In 1815, William Smith sought to explain why fossils appeared in different strata of rocks, putting forth a counter argument to the long-held biblical explanation that the fossils had all been trapped at one time — during the great flood.

New insight into how the Earth was formed came as recently as the late 1970s, when the discovery of high levels of iridium in a particular layer of rock pointed to a devastating asteroid hitting Earth 65 million years ago.

Water
Iain travels to Turkey to discover if a Stone Age civilization survived a catastrophic flood 8,000 years ago, and explains the invention of a true magnetic compass.

He then turns back to Greece, where the ancients used their knowledge of geology to save their land from flooding and defeat their enemies. He also explains how Ephesus, the most important seaport in the eastern Mediterranean in 133 B.C., could become a ghost town only 600 years later. The reason? Silt.

Salt
Did you know that the word "salary" comes from the Latin word for salt? It was how the ancient Romans paid laborers. Salt has been a form of currency for centuries and plays a major role in climate changes that have had sweeping effects on civilization.