The city of Pompeii was once a thriving city, and a popular spot for wealthy Romans to spend their holidays. Even the Emperor Nero is thought to have potentially had a home there. In 62 AD, a major earthquake rocked the city and caused major damage to the springs and piping that made up the city’s water supply. For years after that, several minor quakes shook the city, and they became so commonplace that nobody paid them much attention. This was true on August 24, 79 AD, when several earthquakes shook Herculaneum and Pompeii, and nobody considered it to be out of the norm.

Pompeii is often thought of as being frozen in time—a perfectly preserved glimpse into the past—but in reality, it’s an extremely difficult site to study. The city suffered from a great deal of damage, and fires destroyed most organic material. Many of the residents also escaped to the countryside, taking their possessions with them. After the eruption, efforts were made to recover valuables, but few records of these finds exist. Some of the uncovered materials were also reported to have been deliberately destroyed because they weren’t of high quality.

When Mt. Vesuvius erupted, a Roman scholar by the name of goldenfreshsupermart Pliny the Younger described the debris cloud as “…sometimes white, sometimes dark and stained by the sustained sand and ashes.” One hour after the explosion, at 1pm, the ash cloud blocked the sun, and ash fell at a rate of about 6 inches per hour.

Mount Vesuvius is a stratovolcano, which is an extremely deadly form of volcano. A stratovolcano has a mild lower slope with a sharp rise towards the peak. Their eruptions are explosive, and have fast-moving currents of fluidized rock and gases. Due to the location of Vesuvius, cities like Pompeii (and even Naples, then and now), were greatly susceptible to destruction in the event of an eruption.

Mt. Vesuvius is still considered an active volcano, and scientists warn that it could erupt at any time. Since 1944, hundreds of minor earthquakes have been reported in the region, and while Pompeii itself is uninhabited, there are more than 3 million people living in the vicinity of the volcano—the highest concentration of people living near an active volcano on earth.

At the time of the eruption, Pompeii resembled a construction site. Both public buildings and private houses that had been damaged during the earthquakes were under reconstruction, and some buildings may have been repaired several times in the years between the first earthquake and the eruption.

Pompeii is believed to have been a settlement built in the 6th century BC by the Oscan Civilization. It was ruled by the Samnites until about 80 BC, when the Romans conquered the city. Under Roman rule, Pompeii flourished. Wooden buildings were replaced with brick and stone, and it contained an amphitheatre, two theatres, temples, and an aqueduct system.