@saab,
Yes to that - the old city has long been walled and so fortified. The amphitheater is where Julius Caesar and Pompey were said to have met back in the day.
from wiki -
Ancient and medieval city -
Lucca was founded by the Etruscans (there are traces of a pre-existing Ligurian settlement) and became a Roman colony in 180 BC. The rectangular grid of its historical centre preserves the Roman street plan, and the Piazza San Michele occupies the site of the ancient forum. Traces of the amphitheatre can still be seen in the Piazza dell'Anfiteatro.
At the Lucca Conference, in 56 BC, Julius Caesar, Pompey, and Crassus reaffirmed their political alliance known as the First Triumvirate.[4]
Piazza Anfiteatro and the Basilica di San Frediano.
Frediano, an Irish monk, was bishop of Lucca in the early 6th century.[5] At one point, Lucca was plundered by Odoacer, the first Germanic King of Italy. Lucca was an important city and fortress even in the 6th century, when Narses besieged it for several months in 553. Under the Lombards, it was the seat of a duke who minted his own coins. The Holy Face of Lucca (or Volto Santo), a major relic supposedly carved by Nicodemus, arrived in 742. During the 8th - 10th centuries Lucca was a center of Jewish life, the Jewish community being led by the Kalonymos family (which at some point during this time migrated to Germany to become a major component of proto-Ashkenazic Jewry). Lucca became prosperous through the silk trade that began in the 11th century, and came to rival the silks of Byzantium. During the 10–11th centuries Lucca was the capital of the feudal margraviate of Tuscany, more or less independent but owing nominal allegiance to the Holy Roman Emperor.
end quote
Re the city wall, I've a lot of photos of my own from walking it (or most of it) that I'd like to show, but I'm still futzing or avoiding futzing with my scanner (bad woman).
I was only there four or five days, but managed to love the place. The people in the old city were congenial to me. I figured out that it was in part that I was an older woman alone, not in a group of what the hotel manager called "spaghetti eaters".
More on that city wall via wiki -
The walls around the old town remained intact as the city expanded and modernized, unusual for cities in the region. As the walls lost their military importance, they became a pedestrian promenade which encircled the old town, although they were used for a number of years in the 20th century for racing cars. They are still fully intact today; each of the four principal sides is lined with a different tree species.
from cidadesemfotos.blogspot.com via google images