Imagine walking through the ancient city of Alexandria in Egypt. As you explore, you might notice huge columns and statues along the Great Harbor. To your left, across the bay, is the island where the famous Great Lighthouse once stood. As you wander through the Royal Quarter, you reach the spot where the legendary Library of Alexandria was located. But here’s the twist: this part of Alexandria is now underwater, beneath the Mediterranean Sea.
While many people have heard of Atlantis, a fictional city described by Plato, there are real underwater cities around the world. These include Alexandria, Port Royal in Jamaica, and Pavlopetri in Greece. Scientists study these sunken cities to learn about how people lived in the past, how our planet changes over time, and how these changes affect human life. Many cities were built near water because it was crucial for life, food, and transportation. However, living near water also meant facing the risk of natural disasters that could sink a city.
On June 7, 1692, Port Royal in Jamaica, one of the wealthiest ports at the time, was hit by a massive earthquake. This disaster caused two-thirds of the city to sink into the sea. Today, divers can find buildings and everyday items preserved on the ocean floor, like a 300-year-old pocket watch that stopped ticking when the city sank.
In the winter of 373 BCE, the Greek city of Helike was destroyed by an earthquake that turned the ground into liquid. Moments later, a tsunami hit, submerging Helike and its people into the Mediterranean Sea. Centuries later, Roman tourists would sail over the lagoon that formed and look down at the city’s remains. Earthquakes are sudden and unpredictable, capable of drowning cities in an instant.
Not all sunken cities disappeared due to sudden disasters. Many were submerged gradually over time. Pavlopetri, the oldest known sunken city, was built on Greece’s southern coast 5,000 years ago. It was submerged due to isostatic sea level change. After the Ice Age ended 18,000 years ago, melting glaciers caused global sea levels to rise. Isostatic sea level change happens when the Earth’s crust slowly rebounds from the weight of glaciers, causing some areas to rise and others to sink. Pavlopetri’s ground still sinks about a millimeter per year. The ancient people there slowly moved inland over generations before finally leaving the city around 3,000 years ago.
Today, divers explore Pavlopetri’s streets and peek through ancient doorways into the foundations of houses and community buildings. They learn about the people who lived there by examining what was left behind. Natural events like earthquakes and tsunamis have shaped our continents for millions of years. As global warming speeds up the melting of polar ice caps and raises sea levels, we will need to adapt, just like the people of Pavlopetri did. In the future, some coastal areas we live in today might be claimed by the sea, including cities like Venice, New Orleans, Amsterdam, Miami, and Tokyo. Imagine what future civilizations will discover about us as they explore the ancient ruins of our cities.
Use an online virtual reality platform to explore a recreated sunken city like Alexandria or Pavlopetri. As you navigate through the city, take notes on the architectural features and artifacts you encounter. Discuss with your classmates how these elements provide insights into the daily lives of the people who once lived there.
Work in groups to create a 3D model of a sunken city using materials like clay, cardboard, or digital modeling software. Include key structures such as temples, homes, and marketplaces. Present your model to the class, explaining the significance of each structure and how it might have been used in ancient times.
Choose a real-life sunken city, such as Port Royal or Helike, and research its history, the events that led to its submersion, and what has been discovered there. Create a presentation to share your findings with the class, highlighting the lessons we can learn from these ancient cities.
Conduct a science experiment to simulate the effects of an earthquake and tsunami on a model city. Use a tray of sand to represent the ground and a small container of water to create waves. Observe how the structures are affected and discuss the impact of such natural disasters on ancient and modern cities.
Imagine you are a resident of one of the sunken cities before it was submerged. Write a short story describing your daily life, the events leading up to the disaster, and your thoughts as the city begins to sink. Share your story with the class and discuss how historical events can be brought to life through creative writing.
While touring the remains of ancient Alexandria, Egypt, there are a few things that present-day explorers should look for. First, as you travel along the Great Harbor, keep your eyes open for large columns and statues. Across the bay to your left is the island where the Great Lighthouse once stood. As you make your way through the palaces of the Royal Quarter and reach the area where the Library of Alexandria once stood, be aware of the depth of the Mediterranean Sea, as this section of Alexandria is submerged.
Though people are most familiar with Plato’s fictional Atlantis, many real underwater cities actually exist, such as Alexandria, Port Royal in Jamaica, and Pavlopetri in Greece. Sunken cities are studied by scientists to help us understand the lives of our ancestors, the dynamic nature of our planet, and the impact of each on the other. Water is essential for life, food sources, and transport, leading to the establishment of many cities along coastlines and riverbanks. However, these benefits also come with risks, as natural forces that can sink a city are often nearby.
For instance, on June 7, 1692, Port Royal, Jamaica, one of the richest ports in the world, experienced a massive earthquake that caused two-thirds of the city to sink. Today, many buildings and elements of everyday life remain surprisingly intact on the sea floor, frozen in time, including a 300-year-old pocket watch that stopped at the moment Port Royal slipped beneath the Caribbean.
Similarly, during the winter of 373 BCE, the Greek city of Helike was struck by an earthquake that liquefied the sandy ground beneath it. Minutes later, a tsunami struck, causing Helike and its inhabitants to sink into the Mediterranean Sea. Centuries later, Roman tourists would sail on the lagoon that formed and peer down at the city’s remains. Earthquakes are sudden, unpredictable disasters that can drown cities in an instant.
Fortunately, throughout history, most sunken cities were not submerged by a single cataclysmic event but rather by a combination of more gradual processes. For example, Pavlopetri, the oldest known sunken city, was built on the southern coastline of Greece 5,000 years ago. It serves as an example of a city that was submerged due to isostatic sea level change. When the Ice Age ended 18,000 years ago, glaciers began melting, causing global sea levels to rise. Isostatic sea level change is not caused by meltwater but rather by the Earth’s crust slowly rebounding from the weight of the glaciers, resulting in some areas rising and others sinking. The ground around Pavlopetri is still sinking at an average rate of a millimeter per year. However, the ancient inhabitants were able to gradually move inland over several generations before finally abandoning the city about 3,000 years ago.
Today, divers explore the streets of Pavlopetri and peer through ancient doorways into the foundations of houses and community buildings. They learn about the people who lived there by observing what they left behind. Natural geological events, such as earthquakes and tsunamis, will continue to shape our continents, just as they have for millions of years. As global warming accelerates the melting of polar ice caps and raises sea levels, we will be forced to adapt, much like the inhabitants of Pavlopetri. Undoubtedly, over the coming centuries, some of the coastal areas we inhabit today will eventually be claimed by the water, including cities like Venice, New Orleans, Amsterdam, Miami, and Tokyo. Imagine what future civilizations will learn about us as they explore the ancient ruins of the cities we live in today.
Alexandria – A historic city in Egypt founded by Alexander the Great, known for its ancient library and lighthouse, one of the Seven Wonders of the Ancient World. – Alexandria was a center of learning and culture in the ancient world, attracting scholars from all over the Mediterranean.
Port Royal – A historic harbor town in Jamaica that was a notorious pirate haven in the 17th century before being destroyed by an earthquake. – The earthquake of 1692 devastated Port Royal, sinking much of the city into the sea.
Pavlopetri – An ancient submerged city off the coast of Greece, believed to be one of the oldest underwater archaeological towns in the world. – Pavlopetri provides valuable insights into ancient Greek urban planning and trade.
Earthquake – A sudden and violent shaking of the ground, often caused by movements within the Earth’s crust or volcanic activity. – The earthquake caused significant damage to the historic buildings in the city center.
Tsunami – A series of large ocean waves usually caused by an underwater earthquake or volcanic eruption. – The tsunami that followed the earthquake devastated coastal communities across the region.
Mediterranean – A sea connected to the Atlantic Ocean, surrounded by Europe, Asia, and Africa, known for its historical significance in trade and cultural exchange. – The Mediterranean Sea was a crucial route for merchants and explorers in ancient times.
Glaciers – Large masses of ice that move slowly over land, formed from compacted layers of snow. – The retreat of glaciers is a clear indicator of climate change impacting Earth’s environment.
Sea Level – The average height of the ocean’s surface, used as a standard in measuring land elevation and ocean depth. – Rising sea levels pose a threat to coastal cities and ecosystems around the world.
Natural Disasters – Severe and extreme weather events or geological processes that cause significant damage or loss of life. – Natural disasters like hurricanes and earthquakes have shaped human history by altering civilizations and landscapes.
History – The study of past events, particularly in human affairs, and how they shape the present and future. – Understanding history helps us learn from past mistakes and successes to build a better future.
