Siena is a city in the region of Tuscany, in central Italy. It is located about 80 kilometers south of Florence, and has a population of about 54,000 people. Siena is known for its beautiful setting, on a hilltop overlooking the surrounding countryside. It is also famous for its rich history and cultural heritage, and is home to many famous works of art and architecture. The city is most famous for its cathedral, the Duomo di Siena, which is a UNESCO World Heritage Site. The cathedral is known for its beautiful Gothic architecture and its many works of art, including a famous mosaic floor. Siena is also a popular destination for outdoor activities, with many hiking and biking trails in the surrounding hills.