All roads lead to Rome - and so do these tech trees! From the newspaper to the vending machine, these are 8 amazing Roman technological innovations, in this episode of History Countdown.

Rome delivered fresh water to its people by building massive aqueducts that are still an engineering marvel today.

Did Nero fiddle while Rome burned? Get the full story

Gladiatorial combat takes a turn when women enter the arena.

The Appian Way is the world's first super highway and brought us the first milestone, marking the distance traveled along the road.

Omar explores the workout routines of ancient Roman gladiators and shares a few moves.

The construction of the largest amphitheater in Rome has taken place and now history's most iconic duels commence.

From the Battle of Marathon in 490 BCE to Operation Mincemeat in WWII, discover 7 risky gambles that ended up changing world history.

Commodus revolutionized what it meant to be an emperor by going against the norm and becoming a gladiator.

Built as a temple for the Goddess Athena, the Parthenon is considered one of the greatest examples of Greek architecture still standing.

Two of the most known men in the history of ancient Rome are Gaius Julius Caesar and Spartacus.

in 410 A.D. Alaric and the Visigoths sack Rome after years of holding the city under siege.

It was nearly wiped out during the eruption of Mount Vesuvius in 79 A.D. What is left of this ancient city and will Vesuvius erupt again? Uncover the lost city of Pompeii.

A surprising innovation may have helped the Carthaginians cross the snow-covered terrain of the Alps.

Rome's emperor orders a major renovation to prove himself.

The Roman leader Julius Caesar was stabbed 23 times by a mob of mutinous senators in 44 B.C. Could he possibly have survived long enough to utter his famous last words?

The eruption of Mount Vesuvius in 79 A.D. obliterated the Roman city of Pompeii, burying it under tons of volcanic ash. While many of its resident fled to safety, what happened to those who dared to stay behind?

See how civilizations throughout history have designed and managed their plumbing and waste disposal systems.

Julius Caesar works his way up to becoming one of the most powerful people in Rome.

See what the Roman Empire was like at the time of Jesus' birth in this bonus clip from "Jesus: His Life."

Ancient rulers built luxurious private residences that rival modern-day mansions.

Caesar consolidated his power and made himself dictator. Learn more in this exclusive clip from Ancient Empires.

An underground spiritual movement known as Christianity begins to spread through the empire.

The Roman Coliseum was an engineering marvel designed to seat close to 75,000 people.

When a major health crisis breaks out, a young scientist by the name of Galen is brought in to help.