The main church in Lucca is its cathedral, the Duomo di Lucca, built in the 11th century. The structure stands at one side of the Piazza San Martino, and inside, visitors will find the most revered relic in town: the Holy Face of Lucca (Volto Santo). This wooden cross is said to have been carved by Nicodemus, and although the one on display is a 13th-century copy, it's no less important to the church or town. There are two times each year when the Volto Santo is celebrated, dressed in special vestments in the cathedral. The church was rebuilt in the 14th century, although the campanile (bell tower) from the original structure remains, which is why one arch is quite a bit smaller than the other.
Other points of interest inside the Duomo are paintings by Ghirlandaio and Tintoretto, as well as the 15th-century tomb of Ilaria del Carretto of the Guinigi family. There is a museum in the cathedral as well.
The Piazza dell'Anfiteatro is a large square in the center of historic Lucca. As the name suggests, it was once the site of a Roman amphitheatre, one that was built in the first century and could hold up to 10,000 people. The remains of that structure now lie more than nine feet underground, but the oval shape of the piazza is a direct result of the outline of the amphitheatre. The Piazza dell'Anfiteatro was built in 1830 by demolishing some buildings that had been constructed in the space. It became the site of the town's market, and is the heart of the old city today.
There are a few historic towers inside Lucca's city walls, but the most famous is the Guinigi Tower, which was built in the late 14th century as the place where a family of silk merchants lived and worked. At one time, Lucca had more than 200 such tower homes, but today there are only nine left. The Guinigi family once ruled Lucca, and the family's modern descendants bequeathed the tower to the city. The Guinigi Tower is particularly notable for its impressive rooftop garden. The garden dates from at least the early 17th century, and today has several ancient Holm oak trees growing there. The rooftop garden was renovated in the 1980s and is open to the public.