There’s a fascinating series starting this week on the Mediterranean and Radio 4 (or BBC2 or wherever). Iain Stewart explains that the rise and fall of succeeding civilizations resulted directly from the earth beneath their feet. Unknown to all those thousands of people, their fate was fixed by geology. 

Egypt became the breadbasket of the Med because the Nile flooded every year, bringing thousands of tonnes of fertile silt down from Sudan, which allowed the Egyptians to grow massive surpluses of crops, and grow rich on the proceeds.

Rome was surrounded by volcanoes – some active like Vesuvius, but others extinct. Volcanic ash made wonderful cement – almost as good as the Portland cement patented a couple of thousand years later. With cement the Romans put up such fabulous buildings as the Coliseum and the Pantheon, many of which survive to this day.

The Spanish beaches so popular with today’s tourists were covered with sand washed down as sediment in the rivers after the weathering of mountains inland. Today, however, when the winter storms wash the sand away it is not replenished, because the rivers are blocked by concrete tourist hotels and promenades; so to refurbish the beaches the sand has to be brought in by truck.

Another volcanic area, with Etna on the mainland, and Stromboli and Vulcano offshore, is the island of Sicily, home to the Mafia, delicious wines, and a mountain of salt. Sicily has always been a stepping stone between the northern Mediterranean countries and Africa, and has been overrun by many belligerent countries, right up until the end of the second world war. One of the earliest invasions was by the Phoenicians, who stomped in 3000 years ago from what is now Syria and Lebanon. They realized that food could be preserved with salt, and therefore kept for a rainy day, or transported to places where food was short. They used a Sicilian base, and Sicilian salt, to extend their empire into Spain and Africa.

My favourite people were the Greeks, who gave us mathematics and music, theatre and democracy. What did geology give them? Answer, the mountain ranges, packed with exotic minerals, including silver and lead, which were exposed by earthquakes. The riches they scooped out of the ground allowed the Greeks to build a navy big enough to conquer the Mediterranean from about 700 BC, and they remained top dogs for some 500 years.