Cortona doesn't have its own public transportation system because it doesn't need it. The town is pretty small and is nestled into a triangle on a hill, so having a complex system of trains and buses is just unnecessary. Many of the citizens in the town have their own car or get around by walking. There are taxis in the town, but you might not need it. Other types of public transportation in the area include long range trains from the Eurail, which work very well, and buses connecting towns. If you want to visit another town nearby, you can take a bus with virtually no problems. This is a nice quiet town, and having a bustling public transportation system would just ruin the tranquility. If you will be staying in the town for a few days, it might not be such a bad idea to rent a scooter or a car. Though you probably won't need to use it too often, it is good to have something to get around on. You can't really rely on the taxis too much in Cortona.